Diastereoselective Synthesis of and Mechanistic Understanding for the Formation of 2‐Piperidinones from Imines and Cyano‐Substituted Anhydrides
作者:Michael J. Di Maso、Kevin M. Snyder、Fábio De Souza Fernandes、Ommidala Pattawong、Darlene Q. Tan、James C. Fettinger、Paul Ha‐Yeon Cheong、Jared T. Shaw
DOI:10.1002/chem.201504424
日期:2016.3.24
2‐Piperidinones are synthesized in a single step from imines and 2‐cyano glutaric anhydrides. The reaction provides the products in good diastereoselectivity and generates a quaternary stereogenic center. Substitutions on the anhydride skeleton are well tolerated to provide 2‐piperidinones with three stereogenic centers from a single transformation. The pertinent transition structures have also been
Addition of Reformatsky reagents to 1,1-dicyanoalkenes
作者:Yu Ding、Zongbao Zhao、Chengming Zhou
DOI:10.1016/s0040-4020(97)00023-9
日期:1997.2
Reformatskyreagents are found to react with different 1,1-dicyanoalkenes to afford addition products, and the reaction can be conducted more efficiently in the presence of a catalytic amount of Cp2TiCl2. There is strong evidence to support a SET process in the course of Reformatskyreagent formation.
A process for producing a piperidinecarbinol represented by the general formula (2), which comprises reducing the trans isomer of a compound represented by the general formula (1):
wherein R1 is a hydrogen atom, a lower alkyl group or an aralkyl group, R2 is a hydrogen atom, a lower alkyl group, an aryl group or an aralkyl group, and X is a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a dialkylamino group, an alkylthio group, an arylthio group or CmF2m+1- wherein m is an integer of from 1 to 20.