Metalated nitriles: electrophile-dependent alkylations.
[reaction: see text] Sequential carbonyl addition-conjugate addition to oxonitriles generates a C-magnesiated nitrile exhibiting electrophile-dependent alkylation stereoselectivities. Alkylations with alkyl halides, sulfonates, and ketones proceed with retention of stereochemistry, whereas aldehyde and acyl cyanide acylations proceed with inversion of stereochemistry. BuLi-initiated conversion of the C-magnesiated nitrile to the corresponding N-lithiated nitrile reverses the alkylation stereoselectivity, providing a facile route to diastereomeric nitriles that vary at a single, quaternary stereocenter.
Fleming
Fraser F
FF
Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282-1530, USA. flemingf@duq.edu
Zhang
Zhiyu
Z
Wei
Guoqing
G
Steward
Omar W
OW
D000447:Aldehydes; D000478:Alkylation; D003486:Cyanides; D007659:Ketones / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008968:Molecular Conformation; D009570:Nitriles / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000447:Aldehydes; D003486:Cyanides; D007659:Ketones; D008670:Metals; D009570:Nitriles