Base-Controlled Diastereoselective Synthesis of Either anti- or syn-β-Aminonitriles
摘要:
Deprotonation of secondazty alkane nitriles with nBuLi and addition to aryl imines gives kinetic anti-beta-aminonitriles. Use of LHMDS allows reversible protonation of the reaction intermediate to give syn-beta-aminoriitriles. The pure diastereosiomers can be isolated in good yields, and the mechanism was elucidated.
The first transition-metal-free addition of alkyl nitriles to unactivated irnines was developed using a catalytic combination of 4-MeOC6H4CNa and TMSCH2CO2Et to promote the reaction. The corresponding beta-amino nitriles are obtained in good to almost quantitative isolated yields under mild conditions. A mechanism involving an autocatalytic pathway is proposed on the basis of experimental observations.