A sulfur-assisted five-cascade sequential reaction, wherein the in situ-generated allenyl allyl sulfides undergo thio-Claisen rearrangement, intramolecular Michael addition, and 1, 5-proton migration/aromatization to obtain allyl thiophen-2-yl acetates, propionates, and ketones as the final products, was reported. As a result of the ready availability of starting materials and the extremely sim...

A highly efficient, chemoselective synthesis of a library of polysubstituted pyrroles and tetrahydropyridines has been achieved through the one-pot, multicomponent reactions of ethyl (E)-3-(aryl/alkyl amino) acrylates, 2,2-dihydroxy-1-arylethan-1-ones, and malononitrile under solvent- and catalyst-free grinding conditions. The selective formation of pyrrole or tetrahydropyridines relied on subs...

N-Heterocyclic carbene-catalyzed reaction of 2-aroylvinylcinnamaldehydes with 2-aroylvinylchalcones proceeded via a triple Michael addition and intramolecular lactonization cascade to produce novel 9-(2-aroyl-3-aroylmethyl-1-indanyl)-3-arylindeno[2,1-c]pyran-1-ones in good yields with high diastereoselectivity. This reaction constructed six contiguous stereogenic centers in a single reactive ev...

Highly functionalized multisubstituted 1,4-dihydropyridines 5 have been concisely synthesized in moderate to good yields via L-proline-catalyzed one-pot multicomponent reactions (MCRs) of alkynoates or alkynones 1, amines 2, beta-dicarbonyl compounds 3 and aldehydes 4 under mild conditions. The MCR process involves hydroamination/Knoevenagel condensation/Michael-type addition/intramolecular cyc...

3,4-dihydropyridin-2-ones are of considerable importance due to the large number these core structures exhibiting a diverse array biological and pharmacological activities. The Michael-type addition 1,3-dithiane-2-carbothioates α,β-unsaturated N-tosyl imines, followed by intramolecular annulation driven sulfur leaving group, provides practical reaction cascade for synthesis variety substituted ...

[reaction: see text] A study of the effect of Michael acceptor stereochemistry on the efficiency of intramolecular Morita-Baylis-Hillman (MBH) reactions has been performed. The reactions were catalyzed by a phosphine, and the reaction substrates studied were enones containing a pendant aldehyde moiety attached at the beta-position of the alkene group. In all cases examined with PPh3 as the cata...