Search

A detailed investigation of the liquid-state polymerization of diacetylenes by calorimetric (DSC) and spectroscopic (in situ EPR) thermal analysis techniques is performed. Isoconversional kinetic analysis of the calorimetric data reveals that liquid-state polymerization is governed by a well-defined rate-limiting step as evidenced by a nearly constant isoconversional activation energy. By comparison, solid-state polymerization demonstrates isoconversional activation energy that varies widely, signifying multistep kinetics behavior. Unlike the solid-state reaction that demonstrates an autocatalytic behavior, liquid-state polymerization follows a rather unusual zero-order reaction model as established by both DSC and EPR data. Both techniques have also determined strikingly similar Arrhenius parameters for liquid-state polymerization. Relative to the solid-state process, liquid-state polymerization results in quantitative elimination of the p-toluenesulfonate group and the formation of p-toluenesulfonic acid and a polymeric product of markedly different chemical and phase composition. [ABSTRACT FROM AUTHOR]

The intermolecular aggregation between the solvent and organic molecules is covered in the current article. 4,4′‐(Buta‐1,3‐diyne‐1,4‐diyl)dibenzoic acid (DADBA) was used as an organic molecule and dimethyl sulfoxide (DMSO) as a solvent to create the target compound DADBA‐DMSO. The material's hydrogen bonding and intermolecular aggregation were determined by appropriate characterization methods, including single‐crystal X‐ray diffraction (XRD), Fourier‐transform infrared (FTIR), photoluminescence (PL), and cyclic voltammetry (CV) analysis. Each hydrogen of the carboxylic group is coordinated by oxygen from the DMSO molecule in the stiff planar layer packing that makes up the DADBA‐DMSO crystal structure. [ABSTRACT FROM AUTHOR]

A detailed investigation of the liquid-state polymerization of diacetylenes by calorimetric (DSC) and spectroscopic (in situ EPR) thermal analysis techniques is performed. Isoconversional kinetic analysis of the calorimetric data reveals that liquid-state polymerization is governed by a well-defined rate-limiting step as evidenced by a nearly constant isoconversional activation energy. By comparison, solid-state polymerization demonstrates isoconversional activation energy that varies widely, signifying multistep kinetics behavior. Unlike the solid-state reaction that demonstrates an autocatalytic behavior, liquid-state polymerization follows a rather unusual zero-order reaction model as established by both DSC and EPR data. Both techniques have also determined strikingly similar Arrhenius parameters for liquid-state polymerization. Relative to the solid-state process, liquid-state polymerization results in quantitative elimination of the p-toluenesulfonate group and the formation of p-toluenesulfonic acid and a polymeric product of markedly different chemical and phase composition.

Novel di- and tetra-substituted calix[4]arene derivatives bearing diacetylene moieties at the lower rim of macrocycle were synthesized via the Mitsunobu and Williamson reactions. The dealkylation of diacetylene moieties of calix[4]arene was for the first time discovered in the DMSO—hydrazine hydrate system. An important role in the dealkylation of diacetylene moieties is played by neighboring unsubstituted OH groups at the macrocycle. Blocking of OH groups with butyl substituents and elongation of the linker between the butadiynyl fragments and the macrocyclic platform significantly reduce the affinity of macrocycle to reductive cleavage. The unique reactivity of calix[4]arene in its reaction with hydrazine hydrate was demonstrated in comparison with a model conjugate of diacetylene with 4-tert-butylphenol. The reductive cleavage may proceed via the formation of pyrazole derivative of calix[4]arene. Pyrazole derivatives were the most reactive ones in the reaction with hydrazine hydrate among the studied isostructural calixarenes containing an active α-arylmethyleneoxy moiety. Results of performed quantum chemical calculations allowed us to propose a scheme for the reductive cleavage of oxymethylene derivatives of pyrazole with hydrazine hydrate. [ABSTRACT FROM AUTHOR]

The intermolecular aggregation between the solvent and organic molecules is covered in the current article. 4,4'-(Buta-1,3-diyne-1,4-diyl)dibenzoic acid (DADBA) was used as an organic molecule and dimethyl sulfoxide (DMSO) as a solvent to create the target compound DADBA-DMSO. The material's hydrogen bonding and intermolecular aggregation were determined by appropriate characterization methods, including single-crystal X-ray diffraction (XRD), Fourier-transform infrared (FTIR), photoluminescence (PL), and cyclic voltammetry (CV) analysis. Each hydrogen of the carboxylic group is coordinated by oxygen from the DMSO molecule in the stiff planar layer packing that makes up the DADBA-DMSO crystal structure., (© 2024 John Wiley & Sons Ltd.)

A detailed investigation of the liquid-state polymerization of diacetylenes by calorimetric (DSC) and spectroscopic (in situ EPR) thermal analysis techniques is performed. Isoconversional kinetic analysis of the calorimetric data reveals that liquid-state polymerization is governed by a well-defined rate-limiting step as evidenced by a nearly constant isoconversional activation energy. By comparison, solid-state polymerization demonstrates isoconversional activation energy that varies widely, signifying multistep kinetics behavior. Unlike the solid-state reaction that demonstrates an autocatalytic behavior, liquid-state polymerization follows a rather unusual zero-order reaction model as established by both DSC and EPR data. Both techniques have also determined strikingly similar Arrhenius parameters for liquid-state polymerization. Relative to the solid-state process, liquid-state polymerization results in quantitative elimination of the p -toluenesulfonate group and the formation of p -toluenesulfonic acid and a polymeric product of markedly different chemical and phase composition.

Abstract The utility of the intramolecular Nozaki-type coupling for the synthesis of macrocyclic benzo[ b ]thiophene-fused enediynes has been explored. The starting acyclic enediynes were prepared by the iodocyclization of 2-(buta-1,3-diynyl)thioanisoles followed by the Sonogashira cross-coupling of the resulting iodo-substituted benzo[ b ]thiophene with corresponding acetylenes. We found that Cr(II)-promoted intramolecular cyclization of 7-[2-(iodoethynyl)benzo[ b ]thiophen-3-yl]hept-6-ynal and 7-[3-(iodoethynyl)benzo-[ b ]thiophen-2-yl]hept-6-ynal resulted in the formation of 11-membered macrocyclic enediynes, while both expected 10-membered enediynes cannot be produced under the Nozaki-type reaction from corresponding 6-[3-(iodoethynyl)benzo[ b ]thiophen-2-yl]hex-5-ynal and 6-[2-(iodoethynyl)benzo[ b ]thiophen-3-yl]hex-5-ynal. In the case the reaction was catalyzed by Ni(II), the attack on a proximal triple bond led to the formation of 2-methylenecycloalkane-1-ol fragments, instead of macrocyclization. The DFT analysis of the ring strain in the benzo[ b ]thiophene-fused 10- and 11-membered enediyne-containing cycle provides the plausible explanation of the observed regioselectivity. [ABSTRACT FROM AUTHOR]

We demonstrate a novel strategy for preparing hydrophilic upconverting nanoparticles (UCNPs) by harnessing the photocrosslinking ability of diacetylenes. Replacement of the hydrophobic oleate coating on the UCNPs with 10,12‐pentacosadiynoic acid, followed by overcoating with diacetylene phospholipid and subsequent photocrosslinking under 254 nm irradiation produces water‐dispersible polydiacetylene‐coated UCNPs. These UCNPs resist the formation of a biomolecular corona and show great colloidal stability. Furthermore, amine groups on the diacetylene phospholipid allow for functionalisation of the UCNPs with, for example, radiolabels or targeting moieties. These results demonstrate that this new surface‐coating method has great potential for use in the preparation of UCNPs with improved biocompatibility. Ene‐yne incorporation: Photocrosslinkable diacetylenes can be used as surface coating agents for generating hydrophilic upconverting nanoparticles (UCNPs). After overcoating with photopolymerisable diyne phospholipids, the diyne units on the UCNP surface can be photocrosslinked by irradiation with UV light. The resulting UCNPs demonstrate "stealth" aspects, retain UC luminescence, and have active sites for attachment of bio/radioactive moieties. [ABSTRACT FROM AUTHOR]

Noble metal anisotropic nanostructures have achieved a growing interest in both academic and industrial domains mostly because of their shape-dependent plasmonic properties in the near-infrared region. In this paper, gold and gold-silver anisotropic nanostructures were synthesized in very high shape-yields through a wet, seed-mediated approach based on the use of nearly spherical silver nanoparticles as seeds and chitosan as stabilizing agent. Two chitosans of different origin and molecular properties were selected for the synthetic pathway, leading to the formation of variously sized and shaped end products. In detail, quite homogeneous nanoplatelets of about 25-nm size and 7-nm thickness or nearly spherical, highly porous nanocages of about 50-nm size were obtained, depending on the type of polysaccharide employed. The shape transition towards anisotropic morphologies occurred through a slow, spontaneous process, in which the chitosan nature seemed to play a key role. As expected, both nanoplatelets and nanocages exhibit shape-dependent plasmonic features and surface properties tunable for a variety of application fields. To prove this point, the nanostructures were successfully post-functionalized with poly(10,12-pentacosadiynoic acid) (PCDA), a carboxylic-endowed diacetylene able to anchor on noble metal substrates, to obtain versatile, chromic platforms suitable for sensing and spectroscopic purposes.

Excellent quadratic non-linear optical (ONL-2) properties of the poly(2,5-bis(but-2-ynyloxy) benzoate, containing a polar diacetylene as a chromophore, were found. According with the Maker fringes method, oriented polymer films showing an order parameter of ∼0.23 can display outstanding and stable Second Harmonic Generation (SHG) effects under off-resonant conditions (SHG-532 nm). Also, the macroscopic non-linear optical (NLO)-coefficients were evaluated under the rod-like molecular approximation, obtaining: χzzz(2) and χzxx(2) in the order of 280 ± 10 and 100 ± 10 pm V−1, respectively. The mechanical and chemical properties, in addition to the large ONL-2 coefficients exhibited by this polymer, make it a promising organic material in the development of optoelectronic/photonic devices.

A radiation sensitive material, 10,12-pentacosa-diynoic acid (PCDA), was incorporated into polyvinyl butyral (PVB) films to develop indicators/dosimeters for blood and food irradiation. The present study aims to improve the dosimetric performance of these previously prepared dosimeters and to extend their shelf life by the combination of a radical scavenger, propyl gallate (PG), and a UV absorber, tinuvin-p (TP). The X-ray diffraction (XRD) patterns of the dosimeters were analysed and their dosimetric characteristics were investigated by specular reflectance in the visible spectrum range of 400–700 nm. Upon irradiation, the films turn blue exhibiting two main bands around 670 and 620 nm. Their dose-response functions were fitted by a double exponential growth, 5 parameters, equation. Irradiation temperature influences the dosimeter response at 670 nm without causing thermochromic transition up to 50 °C in poly-PCDA. The useful dose range is 5–4000 Gy depending on the wavelengths of analysis and PCDA content in the films. The overall uncertainty of dose measurement is less than 6% at 2σ. [ABSTRACT FROM AUTHOR]

Chemical investigation of ethyl acetate and n -butanol fractions from methanol extracts from leaves of Hydrocotyle leucocephala Cham. & Schltdl. and aerial parts of H. bonariensis Comm. ex Lam. resulted in the identification of 6 compounds and a putative identification of 12 more, including thirteen glycosylated flavonols (1 – 13), two dibenzylbutyrolactone lignans (14 and 15) and three diacetylenes (16 – 18) based on UPLC-ESI-QToF-MS/MS analysis in the positive and negative ionization modes. In the case of compounds 3, 14 – 18 , their structures were confirmed by analysis of NMR spectra. Compounds 5, 7, 10–12 or isomeric compounds of them were identified for the first time in this genus. The obtained results contribute with chemotaxonomy of Hydrocotyle since flavonoids, dibenzylbutyrolactone lignans, and diacetylenes were characterized, in consonance with other species previously investigated. [Display omitted] • Eighteen compounds were reported from Hydrocotyle leucocephala and H. bonariensis. • Chemical analysis was performed by UPLC-ESI-QToF-MS/MS and NMR. • Compounds 5 , 7 , 10 – 12 , were reported for the first time in Hydrocotyle genus. [ABSTRACT FROM AUTHOR]

The novel ynamide compound, bis-( N -4-methylbenzenesulfonyl, N - n -butyl)-1,3-butadiyne-1,4-diamide ( 3 ), was synthesized and characterized by single crystal X-ray diffraction, 1 H and 13 C NMR, UV-fluorescence spectroscopy, cyclic voltammetry, TGA and DSC techniques. This first reported X-ray structure of a 1,3-butadiyne-1,4-diamide revealed that the amido substituents of 3 adopt a twisted conformation in the crystal with a torsion angle of 76.6° resulting in a molecule with axial chirality. The crystal structure of compound 3 is stabilized by intermolecular CH-π interactions that give pairs of stacked bis-alkyne- 3 units. HOMO/LUMO energy levels of 3 were experimentally determined by means of electrochemical and optical methods to be −5.87/−1.98 eV respectively. The solid state polymerization of the title compound was investigated by differential scanning calorimetry (DSC) revealing that polymerization proceeded simultaneously to the phase transition assigned to the melting of 3 . The solid state polymerization of 3 is discussed of being a topochemically initiated polymer chain reaction that proceeds with a non-topochemical chain growth. [ABSTRACT FROM AUTHOR]

The novel diacetylenes, 9-(5-(4-nitrophenoxy)penta-1,3-diyn-1-yl)-9 H -carbazole ( 1 ) and 4-((5-(9 H -carbazol-9-yl)penta-2,4-diyn-1-yl)oxy)benzonitrile ( 2 ), were prepared and characterized by crystallographic analyses. Compound 1 gave two conformational polymorphs, 1 -(I) and 1 -(II), whose differences were concluded to originate in intermolecular interactions among nitrophenyl groups. Crystal 1 -(I) and 2 had suitable molecular arrangements for solid-state polymerization and polymerized by thermal annealing to give crystalline polydiacetylenes (PDAs). While an arrangement of 1 -(II) was unsuitable for the polymerization. The PDAs showed broad absorption from UV to near IR region (ca. 900 nm), suggesting effective expansion of π-conjugated system by carbazolyl groups. [ABSTRACT FROM AUTHOR]

In further work investigating the intriguing application of diacetylene copolymers in fingermark detection, methods were developed to control (inhibit or enhance) the diacetylene polymerization reaction in fingermarks treated with a mixture of the monomers 2,4-hexadiyne-1,6-bis-(phenylurethane) ( HDDPU) and 2,4-hexadiyne-1,6-bis( p-chlorophenylurethane) ( HDDCPU) in acetone solution. These methods included the use of a humidity chamber to reduce the amount of background development while promoting development on the fingermark, subjecting developed fingermarks to freezing temperatures and using a solvent to remove unreacted monomer in order to inhibit the polymerization reaction. Developed fingermarks were enhanced by conventional lighting (white light, filtered light) and fast Raman mapping, which was shown to be advantageous over FTIR imaging. This study also demonstrated the applicability of diacetylene copolymer solutions in the covert detection of fingermarks on difficult surfaces. Furthermore, fingermarks were successfully developed with good ridge detail on pig skin (used as a model for human skin, a notoriously difficult surface on which to develop fingermarks). [ABSTRACT FROM AUTHOR]

The electronic structure of hyperbranched polymers obtained from para-diaminodiphenyldiacetylenes as AB2 type monomers by one-step polymerization is studied using DFT calculations. Five generations are modelled with optimization at each step. As the molecule grows it shows a helical shape conserving the C2 symmetry with wing like fragments covering the backbone. There is accidental degeneracy of the HOMO with the HOMO-1 and of the HOMO-2 with the HOMO-3. The LUMO is always located at the backbone and the HOMO set at the dianyline-pyrrole fragment. The HOMO-LUMO gap decreases as the molecule grows. Conductivity measurements as well as microscopy studies of para-hyperbranched polymer were carried out. Conductivity measurements as a function of temperature show semiconductor behavior. Optical microscopy reveals a macroscopic crystalline structure of this hyperbranched polymer. [ABSTRACT FROM AUTHOR]

Highlights: [•] The most stable conformers were found from theoretical calculations of diacetylenes. [•] Band shifts and changes in bond lengths were observed when changing the substituent. [•] FT-IR spectra measured by ATR technique and in transmission (KBr) were compared. [•] Fermi Resonance (FR) in Raman and IR spectra was observed and explained. [•] The orientation of diphenylbutadiyne on metal nanoparticles was predicted from SERS. [Copyright &y& Elsevier]

Highlights: [•] A novel ynamine molecule, N1,N1,N4,N4-tetraphenylbuta-1,3-diyne-1,4-diamine (2),was prepared. [•] Two polymorphs of 2 were characterized by single crystal X−ray diffraction technique. [•] Angular dependence on the energy of 2 was revealed by DFT calculation. [Copyright &y& Elsevier]

Abstract: Two diacetylene molecules incorporating an ynamine moiety, 5-(diphenylamino)-2,4-pentadiyne-1-ol (1) and 6-(diphenylamino)-2-methylhexa-3,5-diyn-2-ol (2), were prepared and characterized by single crystal X-ray diffraction, 1H and 13C NMR. The crystal structures of 1 and 2 were solved successfully and were interpreted to be controlled mainly by the intermolecular hydrogen-bondings. The difference in the crystal structures between 1 and 2 was well explained by consideration of the steric repulsion with the methyl groups connected to the carbon atom adjacent to the hydroxyl group in 2. The steric effects of the methyl groups on intra and intercolumnar interaction were found to be important for designing molecular and crystal structures of diacetylene molecules. Although the geometries obtained by DFT calculations showed a good agreement on 2 except for the butadiynyl part, a significant difference was recognized at the environment around the nitrogen of 1. The difference could be explained by the effect of the crystal packing. [Copyright &y& Elsevier]

Abstract: In 1979, Miller and Patel showed that a solution containing two diacetylene monomers, 2,4-hexadiyne-1,6-bis(phenylurethane) (HDDPU) and 2,4-hexadiyne-1,6-bis(p-chlorophenylurethane) (HDDCPU) could be used to develop latent fingermarks on a non-porous surface. In the current work, the same mixture (HDDPU:HDDCPU=10:1, in acetone solution) was used to develop fingermarks on a wide variety of surfaces, both non-porous and porous, including paper. An airbrush system was optimized for the application of the reagent solution. Once the solution evaporates on a surface, the monomers co-crystallize in different ways, depending upon a number of factors, including the surface residue. “Active” co-crystallization leads (with heat or radiation) to the formation of purple polymer, while “inactive” crystallization results in a non-polymerizable white deposit. Fingermark contrast was achieved as a result of active co-crystallization (giving purple polymer) in either the ridges or the furrows, depending upon the surface and other factors. A general observation (supported by spot tests with linseed oil, salt and amino acid solutions) was that on paper, oily materials are more likely to lead to the formation of the purple polymer, while the presence of water inhibits polymerization. However, these observations are not consistent across all other substrates. It is hypothesized that water disrupts hydrogen bonding between diacetylene molecules, and thus prevents the topochemical polymerization of the diacetylenes, which occurs in the solid state between favourably aligned monomers. An interesting observation was the development of fingermarks deposited on paper that had already been treated with the diacetylene reagent. [Copyright &y& Elsevier]

Abstract: An approach to the synthesis of nitronyl nitroxide 2,2′-(buta-1,3-diyne-1,4-diyl)bis(4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole 3-oxide 1-oxyl) (4) was developed. Compound 4 is the first diradical with nitronyl nitroxide groups directly linked through a diacetylene fragment. In solid phase the diradicals are arranged in stacks with parallel Cts, with the distances between the terminal carbon atoms of the neighboring diacetylene groups (T and d) being 6.170 and 4.466Å, respectively, and the angle between the translation vector and the median line passing through the Ch name="sbnd" />Ct of 45.9°. The values of T and d are outside the range of structural criteria allowing a topochemical reaction. Thus UV irradiation does not initiate solid phase polymerization of 4. After exposure at 373K for 1h the crystals of 4 turn dark-brown, become X-ray amorphous and lose the majority of their paramagnetic centers without significantly changing their mass. Upon further heating up to 400–420K the product explodes, releasing about 360kJ/mol of heat. A diluted solution of 4 in 1,4-dioxane produces an EPR spectrum typical of a strong exchange (a multiplet of nine broadened lines with A 4N =0.35mT), indicating the efficiency of the Ch name="sbnd" />Ct as an exchange channel. The character of the experimental μ eff(T) dependence for 4 indicates a strong intramolecular antiferromagnetic-type exchange interaction (J/k B ∼−104K) and the dominating weak intermolecular ferromagnetic exchange. [Copyright &y& Elsevier]

An investigation of the reaction of 1-lithio-1,3-diynes, generated in situ, with nitriles has been carried out. In the case of aromatic nitriles 1-arylalk-1-ene-3,5-diynylamines are formed, which undergo dimerization and cyclization on isolation, giving 3-(alka-1,3-diynyl)-4-(alk-2-ynyl)-2,6-diarylpyridines. The effect of the nature of the substituent in the benzonitrile molecule on the selectivity of the reaction and the yield of the products has been determined. A scheme is proposed for the conversions and the structures of the intermediates have been established. [ABSTRACT FROM AUTHOR]

Abstract: A mechanism of CuCl mediated amine addition to diacetylenes resulting in pyrrole formation has been studied theoretically at B3LYP/6-31G* level of theory. The reaction proceeds via formation of Cu-stabilized carbene intermediates and the formation of the first intermediate is the rate determining reaction step. The catalytic action of CuCl is due to the reduction of activation energy of the carbene intermediate formation from 75.0 to 50.1kcal/mol. The decrease in activation energy is related to the reduction of HOMO–LUMO energy gap between nucleophile and electrophile due to complex formation allowing to catalogue this reaction as interaction between soft acid and base. [Copyright &y& Elsevier]

Combinatorial chemistry was used to develop photocurable thermoplastic polyurethane elastomers through the incorporation of photoreactive diacetylene diols as chain extenders. The methodology applied allowed, in 36 experiments, the choice of the best compromise between mechanical properties and lack of colour. The combinations chosen were scaled up and their properties were evaluated in terms of mechanical properties. The combinatorial approach reduced the estimated time tenfold in developing such type of materials. [ABSTRACT FROM AUTHOR]

Topochemical reactivity of some conjugated diacetylenes with πconjugating substituents upon exposure to γ-radiation, UV-visible radiation and upon thermal annealing is described. Few of the diacetylenes undergo solid state polymerization to provide corresponding polydiacetylenes. The reflectance spectra of the resultant polydiacetylenes showed significant backbone-sidegroup electron coupling. The third-order nonlinear susceptibility of two of the polydiacetylenes obtained were evaluated using Maker's fringe technique. The third-order nonlinear susceptibility, χ(3) value obtained for the two samples were in the order of 10-11 esu for the fully polymerized polydiacetylene films. These values are comparable to the values reported previously for PDAs with aromatic sidegroups. [ABSTRACT FROM AUTHOR]

Noble metal anisotropic nanostructures have achieved a growing interest in both academic and industrial domains mostly because of their shape-dependent plasmonic properties in the near-infrared region. In this paper, gold and gold-silver anisotropic nanostructures were synthesized in very high shape-yields through a wet, seed-mediated approach based on the use of nearly spherical silver nanoparticles as seeds and chitosan as stabilizing agent. Two chitosans of different origin and molecular properties were selected for the synthetic pathway, leading to the formation of variously sized and shaped end products. In detail, quite homogeneous nanoplatelets of about 25-nm size and 7-nm thickness or nearly spherical, highly porous nanocages of about 50-nm size were obtained, depending on the type of polysaccharide employed. The shape transition towards anisotropic morphologies occurred through a slow, spontaneous process, in which the chitosan nature seemed to play a key role. As expected, both nanoplatelets and nanocages exhibit shape-dependent plasmonic features and surface properties tunable for a variety of application fields. To prove this point, the nanostructures were successfully post-functionalized with poly(10,12-pentacosadiynoic acid) (PCDA), a carboxylic-endowed diacetylene able to anchor on noble metal substrates, to obtain versatile, chromic platforms suitable for sensing and spectroscopic purposes. [ABSTRACT FROM AUTHOR]

Excellent quadratic non-linear optical (ONL-2) properties of the poly(2,5-bis(but-2-ynyloxy) benzoate, containing a polar diacetylene as a chromophore, were found. According with the Maker fringes method, oriented polymer films showing an order parameter of ∼0.23 can display outstanding and stable Second Harmonic Generation (SHG) effects under off-resonant conditions (SHG-532 nm). Also, the macroscopic non-linear optical (NLO)-coefficients were evaluated under the rod-like molecular approximation, obtaining: χzzz(2) and χzxx(2) in the order of 280 ± 10 and 100 ± 10 pm V−1, respectively. The mechanical and chemical properties, in addition to the large ONL-2 coefficients exhibited by this polymer, make it a promising organic material in the development of optoelectronic/photonic devices. [ABSTRACT FROM AUTHOR]

Photocrosslinkable diacetylenes were used for the biocompatibilization of upconverting nanoparticles (UCNPs). In their Communication on page 16036 ff., T. Joshi, H. Stephan, K. Zarschler, and co‐workers demonstrate that biomolecular corona‐resistant UCNPs can be generated by first coating the UCNP surface with a mixture of diacetylenic ligands and phospholipids, followed by irradiation with UV light. These ene–yne cross‐linked bright UCNPs contain sites for linking bio/radioactive moieties. [ABSTRACT FROM AUTHOR]