Diastereoselective synthesis of ring-fused thiocarbamates bearing contiguous quaternary carbon centers
摘要:
An efficient DMAP catalyzed tandem aldol/imidization reaction of alpha-isothiocyanato esters with alpha-ketoamides is described, affording ring-fused thiocarbamates bearing contiguous quaternary carbon centers with up to 99% yield in a completely diastereoselective fashion. This method has a wide range of substrate scope and can be used in the synthesis of pyrrolidines. (c) 2013 Elsevier Ltd. All rights reserved.
An efficient and chemoselective C(sp(2))-N bond cleavage of aromatic imidazo[1,2-a]pyridine molecules is developed. A broad scope of amide compounds such as alpha-ketoamides and N-(pyridin-2-yl)arylamides are afforded as the final products in up to quantitative yields. Diverse C-N bond cleavages are controlled by the oxidative species used in this transformation, with various amide products afforded in a chemoselective fashion. A preliminary study indicated that some alpha-ketoamides exhibit anti-Tobacco Mosaic Virus activity for potential use in plant protection.