pgecheverria

Publication date: 4 September 2013
Source:Tetrahedron Letters, Volume 54, Issue 36
Author(s): Konstantin L. Obydennov , Elena L. Klimareva , Marya F. Kosterina , Pavel A. Slepukhin , Yury Yu. Morzherin
The reaction of thioacetamides with dimethyl acetylenedicarboxylate affords 3-oxothien-2-ylidene or 4-oxothiazol-2,5-ylidene derivatives based on the structure of the thioacetamides and the solvent employed. The structural features of the 3-oxothien-2-ylidenes are discussed.

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Publication date: 28 January 2014
Source:Tetrahedron, Volume 70, Issue 4
Author(s): Chuanjie Cheng , Bo Wang , Nan Liu , Wenwen Chen , Xinyan Wang , Yuefei Hu
A novel Pd–C catalytic hydrodechlorination–hydrogenation was developed for a multi-step one-pot transformation of 4-acylpyridines. Under the selected conditions, 4-benzoylpyridines and 4-alkanoylpyridines were chemoselectively converted into the corresponding 4-benzylpiperidine hydrochlorides and α-alkyl-4-piperidinemethanol hydrochlorides, respectively. This catalytic method was performed simply by an addition of 1 equiv of ClCH2CHCl2 to the conventional hydrogenation system and directly gave the crystalline piperidine hydrochlorides in practical quantitative yields.

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