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Synthesis of monomer‐recyclable polyesters solely from CO2 and bulk olefins holds great potential in significantly reducing CO2 emissions and addressing the issue of plastic pollution. Due to the kinetic disadvantage of direct copolymerization of CO2 and bulk olefins compared to homopolymerization of bulk olefins, considerable research attention has been devoted to synthesis of polyester via the ring‐opening polymerization (ROP) of a six‐membered disubstituted lactone intermediate, 1,2‐ethylidene‐6‐vinyl‐tetrahydro‐2H‐pyran‐2‐one (휹‐L), obtained from telomerization of CO2 and 1,3‐butadiene. However, the conjugate olefin on the six‐membered ring of 휹‐L leads to serious Michael addition side reactions. Thus, the selective ROP of 휹‐L, which can precisely control the repeating unit for the production of polyesters potentially amenable to efficient monomer recycling, remains an unresolved challenge. Herein, the first example of selective ROP of 휹‐L is reported using a combination of organobase and N,N′‐Bis[3,5‐bis(trifluoromethyl)phenyl]urea as the catalytic system. Systematic modifications of the substituent of the urea show that the presence of electron‐deficient 3,5‐bis(trifluoromethyl)‐phenyl groups is the key to the extraordinary selectivity of ring opening over Michael addition. Efficient monomer recovery of oligo(휹‐L) is also achieved under mild catalytic conditions. [ABSTRACT FROM AUTHOR]

A new type of UV-curable pressure-sensitive adhesive containing Si atoms (Si-PSAs) was prepared by a solution-free UV-initiated telomerization process of n-butyl acrylate, acrylic acid, methyl methacrylate, and 4-acrylooxybenzophenone using triethylsilane (TES) as a telogen and an acylphosphine oxide (APO) as a radical photoinitiator. Selected commercial adhesion promoters were tested as additives in the formulation of adhesive compositions, i.e., (i) an organic copolymer with polar groups (carboxyl and hydroxyl); (ii) a hydroxymetal-organic compound; and (iii) a quaternary ammonium salt and (iv) a chlorinated polyolefin. No fillers, crosslinking agents, or photoinitiators were used in the adhesive compositions. NMR techniques confirmed the incorporation of silicon atoms into the polyacrylate structure. The influence of adhesion promoters on the kinetics of the UV-crosslinking process of Si-PSAs was investigated by a photo-DSC technique. The obtained Si-PSAs were characterized by adhesion (to steel, glass, PMMA, and PE), tack, and cohesion at 20 °C. Finally, the wetting angle of Si-PSAs with water was checked and their thermal stability was proved (TGA). Unexpectedly, the quaternary ammonium salt had the most favorable effect on improving the thermal stability of Si-PSAs (302 °C) and adhesion to glass and PMMA. In contrast, Si-PSAs containing the hydroxymetal-organic compound showed excellent adhesion to steel. [ABSTRACT FROM AUTHOR]

One-pot syntheses and in situ ultrasonication have been optimized to generate tunable and highly hydrophobic 2,7-octadienyl-ether (ODE) cellulose nanofibrils (CNFs). Using only butadiene sulfone to serve as dual reaction medium and precursor to 1,3-butadiene (1,3-BD) for telomerization with cellulose hydroxyls, the OH-to-ODE conversion significantly improved from ca. 0.7 to 1.2, 1.8, 3.1, and 4.1 mmol of ODE/g-cellulose at 103-110 °C for 1-2 h. Ultrasonication was highly effective and versatile in the direct disintegration of ODE-cellulose (ODE-cell) in nonpolar organic solvents and plant oils into ODE-CNFs as well as pretreating cellulose for improved functionalization. Mixing 2 wt % in situ ultrasonicated 1.2 mmol of ODE/g-cell improved the modulus of polybutadiene six times and the strength of poly(styrene-b-isoprene-b-styrene) three times, whereas in situ ultrasonication of 1.8 mmol/g-cell directly with linseed oil at merely 0.07 wt % created holistic biobased hydrophobic cellulose paper to resist water penetration while also significantly improving the tensile strength. This optimized telomerization and streamlined in situ ultrasonication approach has presented a sustainable synthesis and processing strategy to generate highly hydrocarbon-compatible nanocelluloses previously unattainable.

A combination of electrospray ionization, matrix-assisted laser desorption/ionization and gas chromatography–mass-spectrometry (GC–MS) with electron ionization is used for the analysis of products and intermediates of the isoprene telomerization reaction catalyzed by N-heterocyclic carbene Pd(II) complexes in presence of methanol. It is shown that soft ionization mass spectrometry techniques allow the detection of the main catalytically active cationic intermediate of palladium in real time whereas GC–MS is efficient in the structure determination of hydrogenated telomerization products. The data obtained are confirmed by NMR spectrometry. [ABSTRACT FROM AUTHOR]

Novel method of obtaining functional acrylic resins (FARs) containing carboxyl- and benzophenone groups (in-chain functionalization) and terminal Br atoms was verified. Acrylic oligomers were prepared by a solution-free, UV-initiated telomerization process of basic monomer (n-butyl acrylate) and functional monomers (acrylic acid and 4-acrylooxybenzophenone) in the presence of radical photoinitiator and different amount of tetrabromomethane (CBr4) as telogen. The effect of telogen content on UV-telomerization kinetics as well as physicochemical and thermal (Tg) properties of FARs was investigated. A telogen content higher than 5 wt. parts does not affect the UV-telomerization rate (photo-DSC), the molecular weights of telomers (GPC), or their glass transition temperature (DSC), but it significantly increases the conversion of monomers (up to 88%) and lowers the viscosity of FARs (approx. 6 Pa·s). NMR studies confirmed the inclusion of CBr4 in the structure of functional acrylic telomers. [ABSTRACT FROM AUTHOR]

In the presented study, UV LEDs (365 nm) or a medium-pressure mercury lamp (UV-ABC) were verified as UV radiation sources initiating the photocrosslinking process of varnishes based on novel photopolymerizable phosphorus (meth)acrylate oligomers. Coating formulations were composed of (meth)acrylic/styrene telomers with terminal P-atoms (prepared via a UV phototelomerization process) and different photoinitiators (HAPs, APOs, or APO blends). The kinetics of the UV crosslinking process of the coating formulations depending on UV irradiation and the UV range was investigated by the photo-DSC method. Moreover, the hardness of the varnishes and the conversion of double bonds using the FTIR method were tested. The photopolymerization rate and the photoinitiation index, depending on the type of photoinitiator, were as follows: APOs < APO blends < HAPs. However, the highest coating hardness results were obtained using the least reactive photoinitiator from the APO group, i.e., Omnirad TPOL, or a mixture of three different types of acylphosphine (Omnirad BL 750). The greater effectiveness of the above-mentioned APOs over HAP was also demonstrated when using a UV LED lamp at 365 nm with a low UV dose and UV irradiance, thanks to the presence of phosphoric acid diester in the coating composition, acting as both a telogen and an antioxidant. [ABSTRACT FROM AUTHOR]

A new type of UV-curable pressure-sensitive adhesive containing Si atoms (Si-PSAs) was prepared by a solution-free UV-initiated telomerization process of n-butyl acrylate, acrylic acid, methyl methacrylate, and 4-acrylooxybenzophenone using triethylsilane (TES) as a telogen and an acylphosphine oxide (APO) as a radical photoinitiator. Selected commercial adhesion promoters were tested as additives in the formulation of adhesive compositions, i.e., (i) an organic copolymer with polar groups (carboxyl and hydroxyl); (ii) a hydroxymetal-organic compound; and (iii) a quaternary ammonium salt and (iv) a chlorinated polyolefin. No fillers, crosslinking agents, or photoinitiators were used in the adhesive compositions. NMR techniques confirmed the incorporation of silicon atoms into the polyacrylate structure. The influence of adhesion promoters on the kinetics of the UV-crosslinking process of Si-PSAs was investigated by a photo-DSC technique. The obtained Si-PSAs were characterized by adhesion (to steel, glass, PMMA, and PE), tack, and cohesion at 20 °C. Finally, the wetting angle of Si-PSAs with water was checked and their thermal stability was proved (TGA). Unexpectedly, the quaternary ammonium salt had the most favorable effect on improving the thermal stability of Si-PSAs (302 °C) and adhesion to glass and PMMA. In contrast, Si-PSAs containing the hydroxymetal-organic compound showed excellent adhesion to steel.

A new cationic palladium complex [Pd(η5-C5H5)(PPh2Cy)2]BF4 (I) is prepared by the reaction of [Pd(acac)(PCyPh2)2]BF4 with cyclopentadiene in the presence of BF3·OEt2. The structure of complex I is determined by XRD. Results of the DFT studies at the BP86-D3/def2-TZVP level of theory along with QTAIM and NOCV methods suggest that the hapticity of the cyclopentadienyl ligand in I adopts an intermediate type of coordination between η3 and η5. Compound I demonstrates a catalytic activity in the reaction of 1,3-butadiene telomerization with methanol with a catalyst turnover number up to 43100 (mol·BD)/(mol·Pd) for 6 h and a 76% selectivity to telomeres. [ABSTRACT FROM AUTHOR]

This is the first proof of concept of generating hydrophobic nanocelluloses by facile one-pot solventless telomerization using butadiene sulfone (BDS) to serve the dual functions of 1,3-butadiene (BD) reagent and reaction medium. Optimal telomerization of BD at 6 equiv of 2,7-octadienyl ether (ODE) to amorphous cellulose anhydroglucose (AGU) at 110 °C, or 6ODE110, and then disintegration by shear force yielded ca. 27−41% hydrophobic DMSO, THF, and CHCl3 dispersible nanocelluloses in 3.7, 6.3, and 4.4 nm thickness, respectively. The surface ODE group was evidenced in methylene peaks at 2800−2980 cm−1 and C=C at 1640−1704 cm−1 by FTIR and in both cis and trans C2−C3 double-bond conformations at 700 and 956 cm−1, respectively, by FTIR-ATR. Solution-state 1H NMR elucidated the ODE structure (d6-DMSO; δ 1.47, 1.95, and 2.07 ppm and 4.86, 5.29, 5.61, 5.90, and 6.07 ppm for methylene and olefinic protons, respectively) along with cellulosic protons (δ 4.12, 3.08, 3.28, 3.40, 3.53, 3.19, and 3.93 ppm for H1, 2, 3, 4, 5, 6a, and 6b, respectively), indicating a 30% conversion of surface OH to ODE. ODE-CNFs exhibited far superior thermal stability with a Tmax of 332 °C, 67 °C higher than that of TEMPO-CNFs. Most impressively, 1% ODE-NCs effectively converted hydrophilic solid mica and porous cellulose paper to hydrophobic surfaces with outstanding 102 ± 1 and 94 ± 2° water contact angles, respectively.

Ultra‐low molecular weight (ULMW) CO2‐polyols with well‐defined hydroxyl end groups represent useful soft segments for the preparation of high‐performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2/epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2‐polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2‐polyols with ULMW (580 g mol−1) and high polymer selectivity (>99 %). Moreover, the ULMW CO2‐polyols with various architectures (tri‐, quadra‐, and hexa‐arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2/epoxides, but also lactone, anhydrides etc. or their combinations. [ABSTRACT FROM AUTHOR]

The Pd(II) complexes [Pd(Cp)(L)n]m[BF4]m were synthesized via the reaction of cationic acetylacetonate complexes with cyclopentadiene in the presence of BF3∙OEt2 (n = 2, m = 1: L = PPh3 (1), P(p-Tol)3, tris(ortho-methoxyphenyl)phosphine (TOMPP), tri-2-furylphosphine, tri-2-thienylphosphine; n = 1, m = 1: L = dppf, dppp (2), dppb (3), 1,5-bis(diphenylphosphino)pentane; n = 1, m = 2 or 3: 1,6-bis(diphenylphosphino)hexane). Complexes 1–3 were characterized using X-ray diffractometry. The inspection of the crystal structures of the complexes enabled the recognition of (Cp–)⋯(Ph-group) and (Cp–)⋯(CH2-group) interactions, which are of C–H...π nature. The presence of these interactions was confirmed theoretically via DFT calculations using QTAIM analysis. The intermolecular interactions in the X-ray structures are non-covalent in origin with an estimated energy of 0.3–1.6 kcal/mol. The cationic palladium catalyst precursors with monophosphines were found to be active catalysts for the telomerization of 1,3-butadiene with methanol (TON up to 2.4∙104 mol 1,3-butadiene per mol Pd with chemoselectivity of 82%). Complex [Pd(Cp)(TOMPP)2]BF4 was found to be an efficient catalyst for the polymerization of phenylacetylene (PA) (catalyst activities up to 8.9 × 103 gPA·(molPd·h)−1 were observed) [ABSTRACT FROM AUTHOR]

Removable pressure-sensitive adhesives (PSAs) are used in the production of self-adhesive materials such as protective films, masking tapes or biomedical electrodes. This work presents a new and environmentally friendly method of obtaining this type of adhesive materials, i.e., photochemically induced free radical telomerization. Adhesive binders to removable PSAs, i.e., the photoreactive acrylic telomer syrups (ATS) were prepared from n-butyl acrylate, acrylic acid, and 4-acrylooxybenzophenone. Tetrabromomethane (CBr4) or bromotrichloromethane (CBrCl3) were used as the telogens. ATS was modified with unsaturated polybutadiene resin and a radical photoinitiator. Adhesive compositions were coated onto a carrier and UV cross-linked. The effects of the chemical nature of telomers (i.e., terminal Br or Cl atoms) and their molecular weight (K-value), as well as the cross-linking degree on adhesive properties of PSAs, were studied. It was found that with the increase in telogen content in the system, the dynamic viscosity of ATS and K-value of acrylic telomers decrease, and the conversion of monomers increases. CBr4 turned out to be a more effective chain transfer agent than CBrCl3. Moreover, telomers with terminal Br-atoms (7.5 mmol of CBr4), due to slightly lower molecular weights and viscosity, showed a higher photocrosslinking ability (which was confirmed by high cohesion results at 20 and 70 °C, i.e., >72 h). Generally, higher values of the temperature at which adhesive failure occurred were noted for PSAs based on ATS with lower telogen content (7.5 mmol), both CBr4 and CBrCl3. The excellent result for removable PSA was obtained in the case of telomer syrup Br-7.5 crosslinked with a 5 J/cm2 dose of UV-radiation (adhesion ca.1.3 N/25 mm, and cohesion > 72 h). [ABSTRACT FROM AUTHOR]

Novel method of obtaining functional acrylic resins (FARs) containing carboxyl- and benzophenone groups (in-chain functionalization) and terminal Br atoms was verified. Acrylic oligomers were prepared by a solution-free, UV-initiated telomerization process of basic monomer (n-butyl acrylate) and functional monomers (acrylic acid and 4-acrylooxybenzophenone) in the presence of radical photoinitiator and different amount of tetrabromomethane (CBr4) as telogen. The effect of telogen content on UV-telomerization kinetics as well as physicochemical and thermal (Tg) properties of FARs was investigated. A telogen content higher than 5 wt. parts does not affect the UV-telomerization rate (photo-DSC), the molecular weights of telomers (GPC), or their glass transition temperature (DSC), but it significantly increases the conversion of monomers (up to 88%) and lowers the viscosity of FARs (approx. 6 Pa·s). NMR studies confirmed the inclusion of CBr4 in the structure of functional acrylic telomers.

In the presented study, UV LEDs (365 nm) or a medium-pressure mercury lamp (UV-ABC) were verified as UV radiation sources initiating the photocrosslinking process of varnishes based on novel photopolymerizable phosphorus (meth)acrylate oligomers. Coating formulations were composed of (meth)acrylic/styrene telomers with terminal P-atoms (prepared via a UV phototelomerization process) and different photoinitiators (HAPs, APOs, or APO blends). The kinetics of the UV crosslinking process of the coating formulations depending on UV irradiation and the UV range was investigated by the photo-DSC method. Moreover, the hardness of the varnishes and the conversion of double bonds using the FTIR method were tested. The photopolymerization rate and the photoinitiation index, depending on the type of photoinitiator, were as follows: APOs < APO blends < HAPs. However, the highest coating hardness results were obtained using the least reactive photoinitiator from the APO group, i.e., Omnirad TPOL, or a mixture of three different types of acylphosphine (Omnirad BL 750). The greater effectiveness of the above-mentioned APOs over HAP was also demonstrated when using a UV LED lamp at 365 nm with a low UV dose and UV irradiance, thanks to the presence of phosphoric acid diester in the coating composition, acting as both a telogen and an antioxidant.

Since alkynyl-arylamines are widely used in the chemical industry as pre products, a method of catalytic synthesis of problematic substituted quinolines from aromatic amines containing octadienal substituents has been developed. For this purpose, the processes of N-2,7-octa-dienyl anilines cyclisation under the action of transition metal complexes and telomerisation of arylamines with butadiene in the presence of palladium complexes were studied. Suppose N-2,7-octa-dienyl anilines are synthesised by telomerisation of arylamines with butadiene in the presence of palladium complexes. In that case, the cyclisation process is carried out in the presence of catalytic amounts of Pd(II) complex with dimethyl sulfoxide or nitrobenzene. The conducted research made it possible to study the opportunity of obtaining in one stage aromatic amines substituted in the nucleus by the reaction of butadiene with arylamines in the presence of palladium complexes. The research proved the principal possibility of obtaining ortho-substituted naphthylamines from butadiene and corresponding naphthylamines in one stage. A catalytic method for the synthesis of problematic substituted quinolines in the presence of palladium complexes has been developed. It has been established that the cyclisation of N-octadienyl-arylamines into quinolines proceeds through the stage of Kleisen amino rearrangement. N-2,7-octa-dienyl anilines and their derivatives can be widely used in the paint, pharmaceutical and chemical industries. Quinoline alkenylene derivatives can be used to produce unique polymer materials, hardeners, stabilisers, extractants, sorbing agents, catalysts for the synthesis of polyurethanes, biologically active substances and their analogues. They are pre-products in synthesising alkaloids, medicines and products used in agriculture. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Polar-functionalized polyolefins are high-value materials with improved properties. However, their feedstocks generally come from non-renewable fossil products; thus, it requires the development of renewable bio-based monomers to produce functionalized polyolefins. In this contribution, via the Pd-catalyzed telomerization of 1,3-butadiene and three types of bio-based alcohols (furfuryl alcohol, tetrahydrofurfuryl alcohol, and solketal), 2,7-octadienyl ether monomers including OC8-FUR, OC8-THF, and OC8-SOL were synthesized and characterized, respectively. The copolymerization of these monomers with ethylene catalyzed by phosphine–sulfonate palladium catalysts was further investigated. Microstructures of the resultant copolymers were analyzed by NMR and ATR-IR spectroscopy, revealing linear structures with incorporations of difunctionalized side chains bearing both allyl ether units and polar cyclic groups. Mechanical property studies exhibited better strain-at-break of these copolymers compared to the non-polar polyethylene, among which the copolymer E-FUR with the incorporation of 0.3 mol% displayed the highest strain-at-break and stress-at-break values of 940% and 35.9 MPa, respectively. [ABSTRACT FROM AUTHOR]

The synthesis of novel phosphorus-containing telomers (P-telomers) was conducted via a solution-free UV-initiated telomerization process of butyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, and styrene, different phosphorus telogens (dimethyl phosphite (DMPh), dibutyl phosphite (DBPh), diphenyl phosphite (DPPh) or dibutyl phosphate (DBP)), and a radical photoinitiator-acylphosphine oxide (APO). The course of the UV-phototelomerization process was monitored by photo-DSC and the chemical structures of telomers were assessed by FTIR. Final UV-photocurable varnish compositions consisted of prepared P-telomer syrups, crosslinking monomer (pentaerythritol triacrylate; PETIA), and a radical UV-photoinitiator (α-hydroxyalkylphenone, HAP). The influence of P- telomers on the optical and mechanical features of coatings was investigated. Relatively the highest hardness and satisfactory scratch values, as well as water and solvent resistance, were observed for varnish based on DMPh-telomers. While the strongest adhesive bond to a glass substrate was reported for DPPh-telomers. It is worth pointing out that the P-telomers did not affect the gloss values of varnishes in comparison to the telomer-free reference sample. [ABSTRACT FROM AUTHOR]

In this study, a novel and environmentally friendly method for the preparation of photoreactive pressure-sensitive adhesives (PSAs) was demonstrated. Adhesive binders based on n-butyl acrylate, methyl methacrylate, acrylic acid, and 4-acryloyloxy benzophenone were prepared with a UV-induced telomerization process in the presence of triethylsilane (TES) as a telogen and acylphosphine oxide (APO) as a radical photoinitiator. The influence of TES (0–10 wt. parts) and APO (0.05–0.1 wt. parts/100 wt. parts of monomer mixtures) concentrations on the UV telomerization process kinetics was investigated using a photodifferential scanning calorimetry method and selected physicochemical features of the obtained silicone-(met)acrylate telomeric syrups (K-value, solid content, glass-transition temperature, and dynamic viscosity), as well as properties of the obtained PSAs (Tg, adhesion, tack, and cohesion), were studied. An increase in TES content caused a significant decrease in the Tg values (approx. 10 °C) and K-value (up to approximately 25 a.u.) of the dry telomers, as well as the dynamic viscosity of the telomeric syrups. PSAs were obtained through UV irradiation of thin polymer films consisting only of silicone-(meth)acrylate telomer solutions (without the use of additional chemical modifiers or of a protective gas atmosphere and protective layers). PSAs were characterized by very good adhesion (12.4 N/25 mm), cohesion at 20 °C (>72 h) and 70 °C (>72 h), and low glass-transition temperature (−25 °C). [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By introducing hydroxyl group into PPh3 ligand, a promoter‐free palladium catalytic system based on (p‐HOC6H4)PPh2 ligand was developed for the telomerization of 1,3‐butadiene with CO2. High activity and selectivity towards CO2‐incorporated divinyl δ‐lactone monomer were achieved (TON/TOF: up to 4540/568 h–1; selectivity of δ‐lactone and its isomers: up to 97%). The key role of phenolic hydroxyl group of the ligand in attaining high activity was validated. The good performance of large‐scale reaction in batch reactor demonstrated the potential utility of this simple catalytic system in valorizing CO2 with bulk chemical feedstock. [ABSTRACT FROM AUTHOR]

Novel pressure-sensitive adhesives (PSA) for low energy substrates were prepared by a solvent-free UV-initiated telomerization process using n-butyl acrylate, butyl methacrylate, and lauryl methacrylate (LMA), with trifluoroethanol (TFEtOH) as a telogen, and acylphosphine oxide (APO) as a radical photoinitiator. A crosslinking monomer (an aliphatic urethane acrylate, L9033) and a radical UV-photoinitiator (α-hydroxyalkylphenone) were also tested as components of the adhesive compositions. The influence of LMA and TFEtOH on the UV-phototelomerization process kinetics and the physicochemical features of the obtained fluorotelomers, as well as the concentration of L9033 on the PSA adhesion to a polyethylene surface, were investigated. FT-IR results indicated that the fluorine groups were successfully introduced into the telomer structure. The highest adhesion relative to a polyethylene substrate (12.3 N/25 mm), and the highest hydrophobicity (with a contact angle of 95° for a water/PSA system) were observed for adhesives based on a telomer syrup containing 5 wt. parts of TFEtOH and 30 wt. parts of LMA (per 100 wt. parts of the monomer mixture). Additionally, it was revealed that a higher aliphatic urethane acrylate content and a higher UV dose increased the adhesion feature. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By introducing hydroxyl group into PPh3 ligand, a promoter‐free palladium catalytic system based on (p‐HOC6H4)PPh2 ligand was developed for the telomerization of 1,3‐butadiene with CO2. High activity and selectivity towards CO2‐incorporated divinyl δ‐lactone monomer were achieved (TON/TOF: up to 4540/568 h–1; selectivity of δ‐lactone and its isomers: up to 97%). The key role of phenolic hydroxyl group of the ligand in attaining high activity was validated. The good performance of large‐scale reaction in batch reactor demonstrated the potential utility of this simple catalytic system in valorizing CO2 with bulk chemical feedstock. [ABSTRACT FROM AUTHOR]

Structure-based models or Gō-like models, which are built from one or multiple particular experimental structures, have been successfully applied to the folding of proteins and RNAs. Recently, a variant termed the hybrid atomistic model advances the description of backbone and side chain interactions of traditional structure-based models, by borrowing the description of local interactions from classical force fields. In this study, we assessed the validity of this model in the folding problem of human telomeric DNA G-quadruplex, where local dihedral terms play important roles. A two-state model was developed and a set of molecular dynamics simulations was conducted to study the folding dynamics of sequence Htel24, which was experimentally validated to adopt two different (3 + 1) hybrid G-quadruplex topologies in K+ solution. Consistent with the experimental observations, the hybrid-1 conformation was found to be more stable and the hybrid-2 conformation was kinetically more favored. The simulations revealed that the hybrid-2 conformation folded in a higher cooperative manner, which may be the reason why it was kinetically more accessible. Moreover, by building a Markov state model, a two-quartet G-quadruplex state and a misfolded state were identified as competing states to complicate the folding process of Htel24. Besides, the simulations also showed that the transition between hybrid-1 and hybrid-2 conformations may proceed an ensemble of hairpin structures. The hybrid atomistic structure-based model reproduced the kinetic partitioning folding dynamics of Htel24 between two different folds, and thus can be used to study the complex folding processes of other G-quadruplex structures. [ABSTRACT FROM AUTHOR]

This paper describes an investigation of the catalytic activity of a series of N-heterocyclic palladium(II) complexes with a cinnamyl auxiliary ligand in telomerization of butadiene with methanol. The catalytic activity of the cinnamyl N-heterocyclic complexes was compared with that of PEPPSI type complexes. [ABSTRACT FROM AUTHOR]

3-Ethyl-6-vinyltetrahydro-2H-pyran-2-one (EVP) is a CO2-derived lactone synthesized via Pd-catalyzed telomerization of butadiene. As EVP is 28.9% by weight CO2, it has received significant recent attention as an intermediary for the synthesis of high CO2-content polymers. This article provides an overview of strategies for the polymerization of EVP to a wide variety of polymer structures, ranging from radical polymerizations to ring-opening polymerizations, that each take unique advantage of the highly functionalized lactone. [ABSTRACT FROM AUTHOR]

Since alkynyl-arylamines are widely used in the chemical industry as pre products, a method of catalytic synthesis of problematic substituted quinolines from aromatic amines containing octadienal substituents has been developed. For this purpose, the processes of N-2,7-octa-dienyl anilines cyclisation under the action of transition metal complexes and telomerisation of arylamines with butadiene in the presence of palladium complexes were studied. Suppose N-2,7-octa-dienyl anilines are synthesised by telomerisation of arylamines with butadiene in the presence of palladium complexes. In that case, the cyclisation process is carried out in the presence of catalytic amounts of Pd(II) complex with dimethyl sulfoxide or nitrobenzene. The conducted research made it possible to study the opportunity of obtaining in one stage aromatic amines substituted in the nucleus by the reaction of butadiene with arylamines in the presence of palladium complexes. The research proved the principal possibility of obtaining ortho-substituted naphthylamines from butadiene and corresponding naphthylamines in one stage. A catalytic method for the synthesis of problematic substituted quinolines in the presence of palladium complexes has been developed. It has been established that the cyclisation of N-octadienyl-arylamines into quinolines proceeds through the stage of Kleisen amino rearrangement. N-2,7-octa-dienyl anilines and their derivatives can be widely used in the paint, pharmaceutical and chemical industries. Quinoline alkenylene derivatives can be used to produce unique polymer materials, hardeners, stabilisers, extractants, sorbing agents, catalysts for the synthesis of polyurethanes, biologically active substances and their analogues. They are pre-products in synthesising alkaloids, medicines and products used in agriculture. [ABSTRACT FROM AUTHOR]

The influence of monomer concentration on the properties of radiation-synthesized tetrafluoroethylene telomers in perfluoro-1,3-dimethylcyclohexane has been studied by differential scanning calorimetry and IR spectroscopy, and their thermophysical and structural characteristics have been determined. Using perfluorinated telomers synthesized at various tetrafluoroethylene concentrations, hydrophobic coatings of aluminoborosilicate glass fabric have been obtained with their contact angles reaching 147°. [ABSTRACT FROM AUTHOR]

The Pd(II) complexes [Pd(Cp)(L)n]m[BF4]m were synthesized via the reaction of cationic acetylacetonate complexes with cyclopentadiene in the presence of BF3∙OEt2 (n = 2, m = 1: L = PPh3 (1), P(p-Tol)3, tris(ortho-methoxyphenyl)phosphine (TOMPP), tri-2-furylphosphine, tri-2-thienylphosphine; n = 1, m = 1: L = dppf, dppp (2), dppb (3), 1,5-bis(diphenylphosphino)pentane; n = 1, m = 2 or 3: 1,6-bis(diphenylphosphino)hexane). Complexes 1–3 were characterized using X-ray diffractometry. The inspection of the crystal structures of the complexes enabled the recognition of (Cp–)⋯(Ph-group) and (Cp–)⋯(CH2-group) interactions, which are of C–H…π nature. The presence of these interactions was confirmed theoretically via DFT calculations using QTAIM analysis. The intermolecular interactions in the X-ray structures are non-covalent in origin with an estimated energy of 0.3–1.6 kcal/mol. The cationic palladium catalyst precursors with monophosphines were found to be active catalysts for the telomerization of 1,3-butadiene with methanol (TON up to 2.4∙104 mol 1,3-butadiene per mol Pd with chemoselectivity of 82%). Complex [Pd(Cp)(TOMPP)2]BF4 was found to be an efficient catalyst for the polymerization of phenylacetylene (PA) (catalyst activities up to 8.9 × 103 gPA·(molPd·h)−1 were observed)

The effect of various factors on the activity and selectivity of palladium N-heterocyclic carbene (NHC) complexes in the telomerization of isoprene with alcohols has been studied. The leaving group of the palladium complex does not affect the results of telomerization of isoprene with methanol, which leads to a predominant formation of the head-to-head product. The use of more fatty alcohols as nucleophiles changes the reaction selectivity toward a preferential formation of the head-to-tail isomers. [ABSTRACT FROM AUTHOR]

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N- and С-octadienyl-substituted 1-, 2-naphthylamines and 6-aminoquinolines exhibiting anticorrosion activity in a hydrochloric acid medium were prepared. The reaction of 2-naphthylamine with butadiene in the presence of palladium complexes yields a mixture of 1- or 3-octadienyl-substituted derivatives. The first step of the reaction is the formation of an N-alkadienylated derivative, which subsequently undergoes the palladium-catalyzed Claisen aromatic amine rearrangement. The reaction of α-naphthylamine with butadiene in the presence of a palladium catalyst and trifluoroacetic acid yields N- and C-alkenylation products. In palladium-catalyzed reactions of butadiene with 6-aminoquinoline, N-(2,7-octadienyl)- or N,N-bis(2,7-octadienyl)aminoquinoline was obtained depending on the telomerization conditions. [ABSTRACT FROM AUTHOR]

Polar-functionalized polyolefins are high-value materials with improved properties. However, their feedstocks generally come from non-renewable fossil products; thus, it requires the development of renewable bio-based monomers to produce functionalized polyolefins. In this contribution, via the Pd-catalyzed telomerization of 1,3-butadiene and three types of bio-based alcohols (furfuryl alcohol, tetrahydrofurfuryl alcohol, and solketal), 2,7-octadienyl ether monomers including OC8-FUR, OC8-THF, and OC8-SOL were synthesized and characterized, respectively. The copolymerization of these monomers with ethylene catalyzed by phosphine–sulfonate palladium catalysts was further investigated. Microstructures of the resultant copolymers were analyzed by NMR and ATR-IR spectroscopy, revealing linear structures with incorporations of difunctionalized side chains bearing both allyl ether units and polar cyclic groups. Mechanical property studies exhibited better strain-at-break of these copolymers compared to the non-polar polyethylene, among which the copolymer E-FUR with the incorporation of 0.3 mol% displayed the highest strain-at-break and stress-at-break values of 940% and 35.9 MPa, respectively.

In this study, a novel and environmentally friendly method for the preparation of photoreactive pressure-sensitive adhesives (PSAs) was demonstrated. Adhesive binders based on n-butyl acrylate, methyl methacrylate, acrylic acid, and 4-acryloyloxy benzophenone were prepared with a UV-induced telomerization process in the presence of triethylsilane (TES) as a telogen and acylphosphine oxide (APO) as a radical photoinitiator. The influence of TES (0–10 wt. parts) and APO (0.05–0.1 wt. parts/100 wt. parts of monomer mixtures) concentrations on the UV telomerization process kinetics was investigated using a photodifferential scanning calorimetry method and selected physicochemical features of the obtained silicone-(met)acrylate telomeric syrups (K-value, solid content, glass-transition temperature, and dynamic viscosity), as well as properties of the obtained PSAs (Tg, adhesion, tack, and cohesion), were studied. An increase in TES content caused a significant decrease in the Tg values (approx. 10 °C) and K-value (up to approximately 25 a.u.) of the dry telomers, as well as the dynamic viscosity of the telomeric syrups. PSAs were obtained through UV irradiation of thin polymer films consisting only of silicone-(meth)acrylate telomer solutions (without the use of additional chemical modifiers or of a protective gas atmosphere and protective layers). PSAs were characterized by very good adhesion (12.4 N/25 mm), cohesion at 20 °C (>72 h) and 70 °C (>72 h), and low glass-transition temperature (−25 °C).

The synthesis of novel phosphorus-containing telomers (P-telomers) was conducted via a solution-free UV-initiated telomerization process of butyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, and styrene, different phosphorus telogens (dimethyl phosphite (DMPh), dibutyl phosphite (DBPh), diphenyl phosphite (DPPh) or dibutyl phosphate (DBP)), and a radical photoinitiator-acylphosphine oxide (APO). The course of the UV-phototelomerization process was monitored by photo-DSC and the chemical structures of telomers were assessed by FTIR. Final UV-photocurable varnish compositions consisted of prepared P-telomer syrups, crosslinking monomer (pentaerythritol triacrylate; PETIA), and a radical UV-photoinitiator (α-hydroxyalkylphenone, HAP). The influence of P- telomers on the optical and mechanical features of coatings was investigated. Relatively the highest hardness and satisfactory scratch values, as well as water and solvent resistance, were observed for varnish based on DMPh-telomers. While the strongest adhesive bond to a glass substrate was reported for DPPh-telomers. It is worth pointing out that the P-telomers did not affect the gloss values of varnishes in comparison to the telomer-free reference sample.

Novel pressure-sensitive adhesives (PSA) for low energy substrates were prepared by a solvent-free UV-initiated telomerization process using n-butyl acrylate, butyl methacrylate, and lauryl methacrylate (LMA), with trifluoroethanol (TFEtOH) as a telogen, and acylphosphine oxide (APO) as a radical photoinitiator. A crosslinking monomer (an aliphatic urethane acrylate, L9033) and a radical UV-photoinitiator (α-hydroxyalkylphenone) were also tested as components of the adhesive compositions. The influence of LMA and TFEtOH on the UV-phototelomerization process kinetics and the physicochemical features of the obtained fluorotelomers, as well as the concentration of L9033 on the PSA adhesion to a polyethylene surface, were investigated. FT-IR results indicated that the fluorine groups were successfully introduced into the telomer structure. The highest adhesion relative to a polyethylene substrate (12.3 N/25 mm), and the highest hydrophobicity (with a contact angle of 95° for a water/PSA system) were observed for adhesives based on a telomer syrup containing 5 wt. parts of TFEtOH and 30 wt. parts of LMA (per 100 wt. parts of the monomer mixture). Additionally, it was revealed that a higher aliphatic urethane acrylate content and a higher UV dose increased the adhesion feature.

The kinetics of radiation-initiated telomerization of tetrafluoroethylene in perfluoromethylcyclohexane and perfluoro-1,3-dimethylcyclohexane has been studied, and new perfluorinated telomers of tetrafluoroethylene have been obtained. A detailed study of IR absorption spectra of these telomers confirms the inclusion of fragments of solvent molecules in the composition of the resulting perfluorinated telomers, the absence of double C=C bonds in them, and their more amorphous structure. Analysis of the differences between the IR spectra of the telomers and polytetrafluoroethylene has also suggested that these telomers can be used to create superhydrophobic coatings. [ABSTRACT FROM AUTHOR]

The results of studies on radiation-initiated telomerization of tetrafluoroethylene and on the properties of telomers with reactive terminal hydroxyl, amino, and silane groups are summarized. Prospects for application of the telomers obtained in the design of hydrophobic coatings of glass and polyester fabrics and highly porous ceramic materials based on quartz fibers are assessed. [ABSTRACT FROM AUTHOR]

The dynamics of the human oligonucleotide AG3(T2AG3)3 has been investigated by incoherent neutron scattering in the sub-nanosecond timescale. A hydration-dependent dynamical activation of thermal fluctuations in weakly hydrated samples was found, similar to that of protein powders. The amplitudes of such thermal fluctuations were evaluated in two different exchanged wave-vector ranges, so as to single out the different contributions from intra- and inter-nucleotide dynamics. The activation energy was calculated from the temperature-dependent characteristic times of the corresponding dynamical processes. The trends of both amplitudes and activation energies support a picture where oligonucleotides possess a larger conformational flexibility than long DNA sequences. This additional flexibility, which likely results from a significant relative chain-end contribution to the average chain dynamics, could be related to the strong structural polymorphism of the investigated oligonucleotides. [ABSTRACT FROM AUTHOR]

• Low-surface-area polymer HCP-NHC-3 shows superior catalytic performance and a recorded TON up to 3.1 × 105. • The in situ generated Pd@HCP-NHC-3 can be reused at least 10 runs without reactivity and selectivity loss. • The coordination environment of Pd in heterogeneous catalyst is modified by diene ligands such as 1,3-butadiene or 1-MOD. • Low-surface-area hypercrosslinked skeleton is beneficial to boost the feasibility of heterogeneous telomerization. The main bottlenecks for the industrial application of existing heterogeneous telomerization catalysts are inferior activity, low stability, and poor selectivity. Herein, we develop a heterogeneous catalyst system to obstacle these issues. A low-surface-area hypercrosslinked polymer fabricated by 1,3-diary-imidazolium chlorides IXy·HCl (aryl = 1,6-dimethylphenyl) via the Scholl coupling method was prepared and utilized as solid ligand in pseudo-heterogeneous telomerization of 1,3-butadiene with methanol. Superior catalytic performance (high linear to branched regioselectivity up to 66:1, chemoselectivity up to 98.5%, and a recorded turnover number (TON) up to 3.1 × 105) for the linear product 1-methoxyocta-2,7-diene (1-MOD) was achieved. Moreover, the heterogeneous Pd catalyst could be in situ generated during the telomerization process, which could be reused at least 10 runs without catalytic activity and selectivity loss. Full characterization of catalysts and control experiments results demonstrated that the synergistic effect of low-surface-area hypercrosslinked skeleton and the coordination environment of Pd in heterogeneous catalyst modified by diene ligands such as 1,3-butadiene or 1-MOD was beneficial to boost the feasibility of heterogeneous telomerization. This innovation is a significant step toward the development of high-performance heterogeneous telomerization catalysts for industrial applications. [ABSTRACT FROM AUTHOR]

The current review focuses on the connection of telomerase and telomeres with aging. In this review, we describe the changes in telomerase and telomere length (TEL) during development, their role in carcinogenesis processes, and the consequences of reduced telomerase activity. More specifically, the connection of TEL in peripheral blood cells with the development of aging-associated diseases is discussed. The review provides systematic data on the role of telomerase in mitochondria, the biology of telomeres in stem cells, as well as the consequences of the forced expression of telomerase (telomerization) in human cells. Additionally, it presents the effects of chronic stress exposure on telomerase activity, the effect of TEL on fertility, and the effect of nutraceutical supplements on TEL. Finally, a comparative review of the chronographic theory of aging, presented by Olovnikov is provided based on currently available scientific research on telomere, telomerase activity, and the nature of aging by multicellular organisms. [ABSTRACT FROM AUTHOR]

An efficient method for the selective synthesis of δ‐lactone from CO2 and 1,3‐butadiene was developed by using ultrasmall palladium nanoparticles as a catalyst for the first time. Palladium nanoparticles (1.90±0.39 nm) were generated in situ in the presence of Pd(acac)2, tetrabutylammonium acetate (TBAAc), and PPh3 as the precatalyst, stabilizer, and reductant, respectively. Maximum yield (86 % with 96 % selectivity) with satisfactory conversion (89 %) and turnover number (1271) was achieved under mild conditions. [ABSTRACT FROM AUTHOR]

Novel photopolymerizable phosphorus (meth)acrylate oligomers were verified as anticorrosive and antimicrobial coating materials. Oligomers containing P-atoms were prepared by a solution-free UV-initiated telomerization process of aliphatic (meth)acrylates and styrene in the presence of different organic phosphorus compounds (P-telogens). The influence of the P-telogen structure on the photoaging process of coatings, as well as their anticorrosion and antibacterial properties was investigated. Relatively the highest anticorrosive efficiency was revealed for a varnish based on a telomers syrup containing dibutyl phosphite (DBPh) and dibutyl phosphate (DBP) due to the relatively long alkyl chain. In turn, UV-photocurable coatings exhibited moderate antibacterial and good anti-yeast activity but the best properties were found for the coating with dimethyl phosphite (DMPh). The higher resistance to photodegradation was observed in the case of the diphenyl phosphite (DPPh) due to the large phenyl substituent. Regardless of the structure of the organophosphorus compound, all coatings showed excellent adhesion to the glass substrate. • A varnish binder prepared by a solvent-free UV-telomerization process • Liquid varnishes containing different organophosphorus compounds • Photo-cured varnish coatings with excellent adhesion, hardness, and anticorrosive properties • The coatings with moderate antibacterial and good anti-yeast activities [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Pd-NHC catalysts tested in the telomerization of butadiene with ethanol. • Strong dependance of the product distribution as a function of the NHC size. • Protocol extended to low Pd loading. • Higher branched product and octatrienes yields with Pd-IPr* and -IPr# species. • Excellent reactivity exhibited with solketal using Pd-IMes and -SIMes species. The telomerization reaction of dienes with alcohols mediated by organopalladium complexes represents a versatile method to convert butadiene into value-added chemicals. In this contribution, we have examined the catalytic behavior of a series of well-defined palladium N -heterocyclic carbene precatalysts (Pd-NHC) in the telomerization of butadiene with ethanol. The bulky and less sterically demanding NHC ligands greatly influence yields and selectivity towards the linear product. With more hindered NHC ligands, the branched product is obtained in unprecedented higher amounts. The telomerization of butadiene with the renewable solketal leads to selective and complete conversion to product in minutes. [ABSTRACT FROM AUTHOR]

Thermally curable pressure-sensitive structural adhesives tapes (SATs) were compounded using a solid epoxy resin and multifunctional acrylic telomer solutions (MATs) prepared by a thermally initiated telomerization process in an epoxy diluent containing two kinds of telogens (CBr4 or CBrCl3). Dynamic viscosity, K-value, and volatile mater content in MATs (i.e., MAT-T with CBr4, MAT-B with CBrCl3) were investigated in relation to telogen type and content. The influence of MATs on the self-adhesive features and curing behavior of UV-crosslinked tapes as well as on the shear strength of thermally cured aluminum–SAT–aluminum joints was investigated as well. Increasing the telogen dose (from 5 to 15 wt. parts) caused significant improvement in the adhesion (+315% and +184%), tack (+147% and +298%), and cohesion (+414% and +1716%) of SATs based on MAT-T and MAT-B, respectively. Additionally, MATs with high telogen content (especially the MAT-T-type) improved the resistance of cured joints to aviation fuel, humidity, and elevated temperature. The highest overlap shear strength values were registered for SATs based on MATs containing 7.5 wt. parts of CBr4 (16.7 MPa) or 10 wt. parts of CBrCl3 (15.3 MPa).

A new method of solvent-free acrylic pressure-sensitive adhesives (PSAs) based on UV-induced cotelomerization products was presented. The key acrylic monomers (i.e., n-butyl acrylate and acrylic acid) with copolymerizable photoinitiator 4-acrylooxybenzophenone in the presence of a selected chain transfer agent (tetrabromomethane, TBM) were used in the UV-cotelomerization process. Moreover, two kinds of UV-photoinitiators (α-hydroxyalkylphenones, HPs and acylphosphine oxides, APOs) were tested. Photo-DSC, viscosity, thermogravimetric, and GPC measurements for cotelomers were performed. The kinetics study revealed that the systems with APOs, especially Omnirad 819 and Omnirad TPO, were characterized by a much higher reaction rate and greater initiation efficiency than HPs systems were. Additionally, the APO-based syrups exhibited a higher solid content (ca. 60–96 wt%), a higher dynamic viscosity (5–185 Pa·s), but slightly lower molecular weights (Mn and Mw) compared to HP syrups. However, better self-adhesive features (i.e., adhesion and tack) were observed for PSAs based on cotelomers syrups obtained using APOs with lower solid contents (55–80 wt%). It was found that as the solids content (i.e., monomers conversion) increased the adhesion, the tack and glass transition temperature decreased and the type and amount of photoinitiator had no effect on polydispersity. Most of the obtained PSAs were characterized by excellent cohesion, both at 20 °C and 70 °C.

[Display omitted] A comparative study of N-heterocyclic carbene Pd complexes in the head-to-head isoprene telomerization with methanol revealed significant impact of ligand structure as well as axial group structure on the catalyst activity. Some N,N '-diaryl substituted imidazol-2-ylidene, imidazolidin-2-ylidene and expanded-ring tetrahydropyrimidin-2-ylidene and tetrahydrodiazepin-2-ylidene based ligands were tested to explore the fundamental correlations between structure (ring carbene size along with the substituent sterical and electronic properties) and catalytic activity. [ABSTRACT FROM AUTHOR]

• Emerging PFASs were firstly reported in Fen and Wei rivers. • PFHxS was predominant as a substitute of PFOS in urban areas of Fen and Wei rivers. • Different substitutions of legacy PFAAs were distinct in Fen and Wei river basins. • There were a large amount of PFAA precursors in water samples of Wei River. • A portion of PFOA was contributed by the telomerization products. Legacy per- and polyfluoroalkyl substances (PFASs), mainly long-chain ones, are being substituted by short-chain homologues and novel fluorinated alternatives, whereas their occurrence, spatial distribution, sources and substitution characteristics are not well understood. For the first time, the occurrence and replacing trend of the legacy and novel fluorinated alternatives were examined in the surface water from Fen and Wei rivers, which are the two major rivers located in the underdeveloped and ecology vulnerable areas of central and western China. Results showed that the contamination of legacy and emerging PFASs in both river basins was widespread, and mainly caused by industrial activities. In both rivers, perfluorohexane sulfonic acid (PFHxS), as a substitute for perfluorooctane sulfonic acid (PFOS), was predominant in the urban areas. In the Fen River, more substitutes of PFOS, such as 6:2 fluorotelomer sulfonate (6:2 FTS) and 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA), were distinct, while significant replacing for PFOA with short-chain perfluoroalkyl carboxylic acids (C4-C7) and Ammonium salt of 4,8-dioxa-3H-per-fluorononanoate (ADONA) was observed in Wei River. Besides, advanced oxidation experiment indicated that there were unknown PFASs which could be the precursors of perfluorocarboxylic acids in Wei River. Isomeric analyses indicated that there was contribution of telomerization related sources for PFOA in both rivers, whereas PFOS was mainly from ECF. The estimated total mass discharge of PFASs derived from Wei and Fen River to the Yellow river were 239 and 62.6 kg/year, respectively. [ABSTRACT FROM AUTHOR]

The palladium catalyzed telomerization of butadiene with polyols has been efficiently performed under aqueous and biphasic medium leading to the corresponding octadienylethers. Depending on the choice of the organic co‐solvent and nature of the catalyst employed to promote the reaction, mono‐ to fully substituted ethers could be obtained with high selectivities and yields. Particularly, pentaerythritol was telomerized for the first time allowing the selective synthesis of the corresponding monotelomers by using methylethylketone as organic co‐solvent and the water soluble ligand TPPTS associated to a simple palladium precursor. Polyethers of sorbitol could be efficiently obtained by using a mixture of TPPTS and PPh3 ligands. As seen on the Telo! The palladium‐catalyzed telomerization of butadiene with polyols has been efficiently performed under aqueous and biphasic medium. Particularly, pentaerythritol was telomerized for the first time allowing the selective synthesis of the corresponding monotelomers. [ABSTRACT FROM AUTHOR]

Telomerization is a versatile tool for synthesizing unsaturated ethers, amines and other molecules starting from 1,3‐dienes and respective nucleophiles. The homogeneously catalyzed reaction has been the subject of academic and industrial research for over 50 years, offering a broad variety of substrates, catalysts and process concepts. This Minireview presents the advances and developments in this field over the last decade. The focus was on the conversion of renewable resources, the synthesis of promising new products and the development of efficient process concepts to combine these. Of great value: Telomerization is a versatile tool for synthesizing unsaturated ethers, amines and other molecules starting from 1,3 dienes and respective nucleophiles. The homogeneously catalyzed reaction has been the subject of academic and industrial research for over 50 years, offering a broad variety of substrates, catalysts and process concepts. This Minireview presents the advances and developments in this field over the last decade. [ABSTRACT FROM AUTHOR]

For many years, the efficient use of resources has been a major and permanent challenge for the chemical industry. The implementation of alternative resources such as renewables and carbon dioxide has been a subject of considerable discussion, but also the more efficient use of long known bulk chemicals is of great interest. Among them, 1,3‐dienes such as 1,3‐butadiene from the C4 cut of the naphtha cracker as well as isoprene, piperylene and cyclopentadiene from the corresponding C5 section are important substrates. These dienes are presently employed in various markets, with the greatest importance being in the production of polymers and copolymers. However, homogeneous transition metal catalysis has proven to be a versatile tool to functionalize these important 1,3‐dienes to low molecular weight fine chemicals by introducing, for example, nitrogen, oxygen or silicon. Hence, an upgraded use of the corresponding products as agrochemicals, pharmaceuticals, fragrances or special detergents is close at hand. The main approaches in the topic of homogeneous functionalization reactions of the industrially relevant 1,3‐dienes will be summarized and discussed within the present article. Besides that, novel applications including renewable 1,3‐dienes, for example β‐myrcene and β‐farnesene, as well as the application of CO2 in telomerization, will be critically discussed. Going all the way! Homogeneous transition metal catalysis is a very potent tool to functionalize 1,3‐dienes to low molecular weight fine chemicals. This Review covers functionalization reactions of the fossil‐based 1,3‐butadiene, isoprene, piperylene, cyclopentadiene and bio‐mass based β‐myrcene and β‐farnesene. A differentiation between industrially established processes and those that have been tested on laboratory and miniplant scale in academia is made. The different examples are presented in a well‐structured order and critically discussed, stimulating scientists to pay more attention to these chemicals for producing versatile compounds through homogeneous catalysis. [ABSTRACT FROM AUTHOR]