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Herein we report an organophotocatalyzed one-pot approach for the synthesis of γ-undecalactone from 1-octanol and methyl acrylate using continuous-flow photoreactors. By using readily available and inexpensive 4CzIPN as the photocatalyst, the α-C-H alkylation reaction can be easily scaled up to 3 mol with a catalyst loading of 0.08%. [Display omitted] γ-Undecalactone has a powerful peach aroma and is widely used in the field of flavor and pharmaceutical industry. Herein we report an organophotocatalyzed one-pot approach for the synthesis of γ-undecalactone from 1-octanol and methyl acrylate using continuous-flow photoreactors. By using readily available and inexpensive 4CzIPN as the photocatalyst, the α -C-H alkylation reaction can be easily scaled up to 3 mol with a catalyst loading of 0.08 %. [ABSTRACT FROM AUTHOR]

An efficient method for the α-chlorination of ketones under basic conditions is described using methyl chlorosulfate. Its applicability for the chlorination of other functional groups has also been studied and it is equally useful for the synthesis of α-chloroesters and amides. Methyl chlorosulfate is described for the first time as a positive chlorine source. Some aldol reactions which occur during the chlorination of some substrates are also reported. [ABSTRACT FROM AUTHOR]

A series of novel ( E )-5,5-dimethyl-3-styrylcyclohex-2-en-1-ol dienes were synthesized by reduction of the respective ketones and their Diels–Alder reactivity explored with N -phenylmaleimide and methyl acrylate. Consequently, two groups of novel products were synthesized in high yields. In reactions with N -phenylmaleimide, the initially formed cycloadducts undergo an additional in situ lactonization to give tricyclic lactone systems, due to spontaneous attack of the allylic hydroxyl on the neighboring carbonyl group of the dienophile residue. All reactions proceeded stereoselectively to give solely the endo products. [ABSTRACT FROM AUTHOR]

Described herein is a rhodium(III)-catalyzed coupling of aromatic ketazines or oximes with 2-vinyloxirane via directed C–H activation. This reaction proceeds efficiently under mild conditions with a low catalyst loading, especially in conditions with room temperature in the absence of additives for aromatic ketazines. A wide range of substituted substrates is supported and a possible mechanism is proposed according to the experimental results of kinetic isotopic effect, reversibility studies, and catalysis with rhodacycle intermediate c1 . [ABSTRACT FROM AUTHOR]

A series of 1,3,4-trialkyl-1,2,3-triazolium ionic liquids were synthesized via click chemistry and used as reaction media for the Morita–Baylis–Hillman (MBH) reaction. [ABSTRACT FROM AUTHOR]

Abstract: rac-BINAP-PdCl2 catalytic system catalyzed Heck reaction of 3-formylquinolin-2-yl chlorides with methyl acrylate in DMA is described to the synthesis of methyl 3-(3-formyl-quinolin-2-yl)-acrylates, in good to excellent yields. The reaction could be also extended with other activated alkenes to afford Heck products. Fused-benzene ring in heterocyclic and carbocyclic moieties was found to enhance the yields. [Copyright &y& Elsevier]

Abstract: The catalytic role of cucurbit[n]urils on the reactivity and stereoselectivity of the [4+2] cycloaddition reaction between cyclopentadiene and methyl acrylate has been examined with density functional calculations. [Copyright &y& Elsevier]

Abstract: Hydroaroylation of methyl acrylate 2a to give the α-aroyl esters 4 took place in the three-component reaction of 2a, aroyl chlorides 1, and Et2MeSiH in the presence of 1mol% of [Rh(cod)(PR3)2]OTf (cod=1,5-cyclooctadiene, OTf=OSO2CF3, R=Ph (3a), OPh (3b)) in CH2Cl2. GC and 1H NMR investigation revealed that the rhodium-catalyzed hydroaroylation proceeds via two successive transformations, that is, hydrosilylation of 2a to afford silyl enol ether 5a followed by C–C bond formation between 5a and 1a. [Copyright &y& Elsevier]

Abstract: A theoretical study of the mechanism, stereoselectivity, Lewis acid catalysts and solvent effects on the Diels–Alder reactions of methyl acrylate and methyl methacrylate with furan has been carried out through DFT calculations at the B3LYP/6-31G∗ level of theory. Bond order and charge transfer analysis indicate that these reactions take place via an asynchronous concerted mechanism. The Lewis acid catalyst changes the nature of the mechanism but not the stereoselectivity. The inclusion of solvent effects does not change the obtained results in the gas phase study. [Copyright &y& Elsevier]

Abstract: A simple and straightforward synthesis of symmetrical 3,3-diarylacrylates based on a Heck-Matsuda reaction of arenediazonium salts bearing electron-donating groups with methylacrylates is described. The reaction employs Pd(OAc)2 as catalyst and goes to completion within 1h affording the corresponding unsaturated diaryl esters in good to high yields. This method permitted the expeditious and efficient synthesis of the anticancer 3-arylindanone 5 in two operative steps in 43% overall yield. [Copyright &y& Elsevier]

Abstract: Exploratory studies towards the preparation of potential HIV-1 protease and integrase inhibitors have led to the synthesis of Baylis–Hillman-derived N,N′-disubstituted piperazines. X-ray crystallographic, computer modelling and NMR techniques have been used to elucidate questions concerning configurational preferences, reaction pathways and the apparent difference in susceptibility towards aza-Michael reactions exhibited by methyl acrylate and methyl vinyl ketone (MVK) derived Baylis–Hillman substrates. [Copyright &y& Elsevier]

Abstract: A heterogeneous Lewis acid catalytic system has been developed by incorporating gadolinium triflate on to poly[styrene-co-(1-((4-vinylphenyl)methyl)-3-methylimidazolium) tetrafluoroborate] (1-Gd(OTf)3), and the catalytic activity of this system has been examined for Michael additions of amines and thiols to α,β-unsaturated esters and acrylonitrile. The reactions proceed in moderate to excellent yields in the presence of catalytic system 1-Gd(OTf)3. The catalytic system could be efficiently recycled and reused. [Copyright &y& Elsevier]

Regio- and stereoselective cycloaddition of methyl acrylate to C-glycosyl nitrones derived from d-galactose and d-glucose, giving 5-methoxycarbonyl-3-(pentoglycos-5-yl or pentitol-1-yl)isoxazolidines, is reported. Transformation of one of them into a 4-hydroxy-2-(pentoglycos-5-yl)pyrrolidine derivative, potentially useful in a route to polyhydroxy-perhydroazaazulenes, was achieved. [Copyright &y& Elsevier]

We have found that in the Baylis–Hillman reactions of N-arylidenediphenylphosphinamides 1 with methyl vinyl ketone (MVK), methyl acrylate or acrylonitrile, the Lewis base and solvent can significantly affect the reaction rate. Using PPh3 as Lewis base in the reaction of 1 with MVK in DMF, THF or MeCN, the normal Baylis–Hillman adduct 2 was formed in very high yield. In the Baylis–Hillman reaction of 1 with methyl acrylate, the Lewis base Ph2PMe must be used in order to get a high yield of the Baylis–Hillman adduct 3. On the other hand, for the reaction of N-arylidenediphenylphosphinamides 1 with acrylonitrile, DABCO is the best Lewis base giving the corresponding Baylis–Hillman adducts 4 in high yields. [Copyright &y& Elsevier]

Abstract: Mizoroki–Heck cross-couplings of aryl halides in the presence of a palladium catalyst supported on a rasta resin bearing diphenylphosphanyl ligands are reported. In particular, we show that tiny amounts of soluble palladium species leached from the polymeric support catalyze the reaction. A one-pot two steps preparation of alkenes from aryl bromides using a Finkelstein halogen exchange reaction is also described. [Copyright &y& Elsevier]

Novel routes to the synthesis of spirothiazolidinones have been designed using a Michael addition reaction followed by a Dieckmann condensation and a Claisen type condensation reaction. [Copyright &y& Elsevier]