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Abstract: The Biginelli 3,4-dihydropyrimidin-2(1H)-one was converted to various C2-multifunctionalized pyrimidines via the dehydrogenation and Mitsunobu reaction using amines, alcohols, phenols and carboxylic acids as nucleophiles. A possible mechanism was also proposed to rationalize the formation of products. [Copyright &y& Elsevier]

Abstract: A novel traceless route to 3,5-disubstituted-1,2,4-triazoles has been described, which allows the incorporation of two elements of diversity. This method provided a library of 3,5-disubstituted-1,2,4-triazoles with high yields and purity. [Copyright &y& Elsevier]

Abstract We report a rhodium-catalyzed ortho C(sp 2)-H borylation of 2-phenylpyridines using commercially available N-heterocyclic carbenes (NHCs) as ligand and pinacolatodiboron (B 2 pin 2) as borylating reagent. The reaction could take place at room temperature, tolerating a wide range of functionalities and affording ortho borylated products in moderate to excellent yields. The current method is also applicable to gram-scale reaction with reduced catalyst loading. Graphical abstract Image 3 [ABSTRACT FROM AUTHOR]

Pyrimidin-2-yl tosylates which are successfully applied as the electrophiles instead of halides coupled with olefins via Pd(PPh 3 ) 2 Cl 2 catalyzed Mizoroki–Heck reaction conditions to give the corresponding C2-alkenyl pyrimidine derivatives with high β -regioselectivity. This protocol proves to be tolerant of various pyrimidin-2-yl tosylates as well as various olefins including styrene derivatives, aliphatic olefins (vinyl cyanide, methyl acrylate, ethyl acrylate, n -butyl acrylate, butyl vinyl ether, 1-hexene and 1-octene). [ABSTRACT FROM AUTHOR]

Abstract: A simple and highly selective colorimetric sensor (L1) bearing thiosemicarbazide moiety as binding site and nitrophenyl moiety as signal group were synthesized. Sensor L1 showed great colorimetric single selectivity and high sensitivity for mercury cation in DMSO and DMSO/H2O binary solutions. When Hg2+ was added to the DMSO solution of L1, dramatic color change from brown to colorless was observed. While the cations Ca2+, Mg2+, Cd2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Ag+ and Cr3+ could not cause any distinct interferer toward the recognition process for Hg2+. The detection limit is allowable to 5.0×10−6 and 1.0×10−7 M level of Hg2+ according to visual color change and UV–vis change, respectively. The recognition mechanism of the sensor toward mercury cation was evaluated in DMSO solutions by UV–vis and 1H NMR. The sensor selectively sense Hg2+ via the formation of a stable 1:1 complex through Ce:glyph name="dbnd" />O group with Hg2+. When these complex bonds formed, the sensor carried out an ICT transition induced color change. [Copyright &y& Elsevier]

[Display omitted] • Inverse vulcanisation by photopolymerisation in solvent systems. • Allows solid crosslinkers, such as β-carotene, to react at RT. • Widely transferrable across liquid, volatile and even gaseous systems. • Prevents the production of the toxic H 2 S by-product; • Crucial role of trace water in IV reaction under thermal conditions. Inverse Vulcanisation (IV) under neat reaction conditions (without solvent) has enabled the research and development of the fundamental chemistry as well as the generation of unique sulfur-rich polymers with unprecedented properties. However, such bulk polymerisation can be problematic, especially with high molecular weight. The energetics of the thermal polymerisation process, combined with poor heat control of solvent-free polymerisation, cause risks of dangerous auto-acceleration if the process is scaled up. The required high temperatures (>160 °C or 135 °C even with catalysts), exceed the boiling point of most commonplace organic solvents, preventing implementation of solvents for IV under thermal conditions. We report here a photo-induced IV polymerisation in solvent at room temperature. The reactions proceed smoothly and efficiently with excellent yields, despite the potential negative factors of reflection, refraction, and low absorption intensity of light by these organic solvents, opening an attractive avenue for the preparation of functional sulfur-rich polymers as well as their potential applications. The extension of crosslinkers to the value-added C5 fraction of industrial byproduct and β-carotene showcase the benefit of this low temperature protocol. Mechanistic study reveals that the moisture in both substrates and solvents might play a key role for the generation of toxic H 2 S by-product in IV reaction under thermal conditions, with photopolymerisation remaining un-affected. This protocol not only extensively expands the scope of crosslinkers for the IV reaction together with resultant polymers, but also provides a potential scale-up route for industrial application by avoiding the generation of toxic H 2 S by-product and possible explosion risk with high temperature. [ABSTRACT FROM AUTHOR]

• Direct allylation of chiral oxazolidinone with aldehydes and olefins. • I 2 -catalyzed amide-aldehyde-olefin condensation. • From inexpensive and abundant un-activated olefins. An iodine-catalyzed direct allylation of chiral oxazolidinones with aldehydes and alkenes has been developed. The reaction proceeds, without use of any bases or metals, directly converted the 3-chiral oxazolidinones into N -allylated oxazolidinones. Additionally, the 3-chiral allylamine skeleton was constructed and the diastereomers were isolated by simple column chromatography. [ABSTRACT FROM AUTHOR]

Abstract KMnO 4 -mediated oxidative C N bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Methylation of quinoline-2-thione under mild and environmentally friendly conditions. • DMSO as readily available source of methyl group. • Using UV light without metal- and dye-photocatalyst. Abstract An UV-light-induced S- methylation of quinoline-2-thione was completed by using dimethyl sulfoxide as methyl reagent. A series of quinoline methyl sulfides were prepared in moderate to good yields under environmentally friendly and mild conditions. [ABSTRACT FROM AUTHOR]

Ni-catalyzed Suzuki–Miyaura cross-coupling reactions of pyrimidin-2-yl phosphates, tosylates and pivalates with arylboronic acids were described. A wide array of functionalized pyrimidines have been prepared in impressive yields and show good tolerance towards wide substrate scope. [ABSTRACT FROM AUTHOR]

CuSO 4 ·5H 2 O and NaAsc catalyzed hydroxylation and C–O/C–S cross-coupling reactions of aryl halides with phenols or 4-methylbenzenethiol were described. A wide range of substrates and test cases highlight the synthetic utility of the approach. A series of phenols, diaryl ethers, alkylaryl ethers, and diaryl thioethers were synthesized in high yield. [ABSTRACT FROM AUTHOR]

(2-Chlorobenzoyloxy)copper(I) exhibited high activity towards the challenging amination of 2-amino pyrimidines with aryl halides. Herein, secondary and tertiary amines were selectively produced by using potassium phosphate and sodium- t -butoxide. Potassium phosphate favored the formation of secondary amines, whereas tertiary amines were favored when sodium- t -butoxide was used. [ABSTRACT FROM AUTHOR]

Iodine-catalyzed three component reaction of quinazoline-2,5-diones, aldehydes, and styrenes provides allylamine derivatives was described. Both paraformaldehyde and ethyl glyoxalate can be applied in this reaction with simple styrenes with high regioselectivity. [ABSTRACT FROM AUTHOR]

Abstract: Copper-catalyzed intermolecular C–N bond-forming reactions between aryl iodides and amides are described using sodium ascorbate, which is both cheap and nontoxic, as the additive. A variety of functionalized amides including some practical, unique secondary amides, such as N-arylacrylamides and 4-amido-N-phenylbenzamides, which are difficult to obtain by the classical methods, are prepared. Furthermore, some tertiary amides are prepared by using copper thiophenecarboxylate. [Copyright &y& Elsevier]

Abstract: A domino S–N and C–N coupling/oxidative aromatization process to synthesize 2-aminothio-phenylpyrimidines and 2-amino-phenylpyrimidines by S–N and C–N cross-coupling reactions is described. This methodology couples 3,4-dihydropyrimidine-2-thiones and secondary amines catalyzed by molecular iodine. Remarkably the C–N coupled product was obtained via a desulfitative coupling-aromatization reaction in one-pot reaction. [Copyright &y& Elsevier]

Abstract: A Cu (I) generated in situ from Cu(OAc)2·H2O/sodium ascorbate catalyzed one-pot multicomponent reaction for the synthesis of a series of N-functionalized 1,2,3-triazoles with 3,4-dihydropyrimidione from 3,4-dihydropyrimidiones, paraformaldehyde, sodium azide and alkynes is described. Remarkably N-functionalized 1,2,3-triazoles with amide were prepared by this method. This procedure eliminates the need to handle organic halides or organic azides, as they are generated in situ, making this already powerful click process even more user-friendly and safe. [Copyright &y& Elsevier]

Abstract: N-Alkoxymethylation of heterocyclic compounds with diethyl phosphite via cleavage of P–O bond was investigated and a series of N3-ethoxymethylated heterocyclic compounds were synthesized. A mechanism in which diethyl phosphite acts as an efficient surrogate of ethanol was proposed and supported by several evidences. [Copyright &y& Elsevier]

Abstract: A tandem cyclization of imines with N-vinyllactams induced by TBPA+ was investigated, and a series of 2-methyl-4-anilino-1,2,3,4-tetrahydroquinolines were synthesized based on a domino process in which N-vinyllactams serve as an acetaldehyde surrogate. A single electron transfer mechanism was proposed and radical cation salt acts as both a Lewis acid and one electron oxidant to induce such transformation. [ABSTRACT FROM AUTHOR]

Abstract: Polymer bound sulfonic acid was prepared on polystyrene–poly(ethylene glycol) (PS–PEG) resin. The PS–PEG-bound sulfonic acid exhibited good catalytic activity in the Biginelli-type reaction for the synthesis of 3,4-dihydropyrimidinones with good yield and good recyclability (six times). This method presents a remarkable technique toward an efficient synthesis of 3,4-dihydropyrimidinones. [Copyright &y& Elsevier]

A multifunctional luminescent material (BC–B) was synthesized, which exhibits aggregation-induced emission (AIE) enhancement property in high water fraction. The AIE shows a significant impact on the intramolecular charge transfer (ICT) process by controlling intramolecular motion. The above result is demonstrated by density functional theory (DFT) calculations and single-crystal X-ray diffraction. To decrease the influence of AIE on ICT, the probe BC-B is exploited as turn-on fluorescent probe for hydrazine (N 2 H 4) in DMSO/PBS buffer (6/4, v/v) and displays high sensitivity and selectivity. Besides, the fluorescence emission shows a good linear response (R2 = 0.9960) in the range of 0–35 μM with the low detection limit of 1.29 ppb, which is significantly below the acceptable limit for hydrazine (10 ppb) set by the USEPA. Image 1 • A novel fluorescent probe BC-B was synthesized and showed aggregation-induced emission (AIE) enhancement performance. • The influences of the AIE on the ICT process were demonstrated by DFT calculations and single-crystal X-ray diffraction. • The probe BC-B was applied to turn-on detection of N 2 H 4 by lessening the AIE influences on the ICT process. [ABSTRACT FROM AUTHOR]