Synthesis of chiral 1,4-dihydropyridines by diastereoface-selective asymmetric addition to nicotinic amides
作者:Shinji Yamada、Mayumi Ichikawa
DOI:10.1016/s0040-4039(99)00683-8
日期:1999.5
Diastereoface-selective asymmetric addition of organometallic reagents to pyridinium salts of 1 and 2 was performed to give chiral1,4-dihydropyridines in good regio- and stereoselectivities. The absolute configuration of the newly-produced chiral center was determined by X-ray analysis after derivation to menthyloxycarbamate 10. Neighboring group participation of the thiocarbonyl group to the pyridinium
Regio- and stereoselective synthesis of 1,4-dihydropyridines by way of an intramolecular interaction of a thiocarbonyl or carbonyl with a pyridinium nucleus
Chiral 1,4-dihydropyridines were prepared by the regio- and stereoselective addition of ketenesilylacetals and organometallic reagents to pyridinium salts. In the addition reaction, an intramolecular interaction between the thiocarbonyl or carbonyl with the pyridinium nucleus plays an important role in bringing about the selectivities. The absolute configuration of the newly produced stereogenic