Cyclization reactions of nitriles. 50. Regioselectivity in the reactions of quaternized pyridin-3-ylidene malonitrile and cyanoacetate ester derivatives with 1,3-dicarbonyl compounds. Crystal structure of 2-amino-3,5-dicarboethoxy-6-methyl-4-(1-methylpyridinium-3-yl)-4H-pyran iodide
been developed for the reductive alkylation of malononitrile with aromatic aldehydes. This new procedure has vastly improved the yield and efficiency of the process, and increased the scope of the aromatic aldehydes. Incorporating water as the catalyst in ethanol for the condensation step allows stoichiometric amounts of malononitrile and aldehyde to be employed. The reduction step takes place quickly
An unprecedented alkylation reaction of malononitriles with enantioenriched primary allylic amines has been developed in a stereospecific manner through palladium-catalyzed sp(3) C-N bond cleavage without additives at room temperature.
Selective reduction of three kinds of substrates were studied to evaluate the reducing abilities of N,N-dimethyl-benzimidazolidine (DMBI), 2-phenylbenzimidazoline (PBI) and 2-phenylbenzothiazoline (PBT). As hydride donors, these three five-membered heterocyclic compounds performed different reducing abilities depending on the substrates. (C) 2012 Elsevier Ltd. All rights reserved.