Metalated nitriles: cation-controlled cyclizations.
Judicious choice of cation allows the selective cyclization of substituted gamma-hydroxynitriles to trans- or cis-decalins and trans- or cis-bicyclo[5.4.0]undecanes. The stereoselectivities are consistent with deprotonations generating two distinctly different metalated nitriles: an internally coordinated nitrile anion with BuLi, and a C-magnesiated nitrile with i-PrMgCl. Employing cations to control the geometry of metalated nitriles permits stereodivergent cyclizations with complete control over the stereochemistry of the quaternary, nitrile-bearing carbon.
Fleming
Fraser F
FF
Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282-1530, USA. flemingf@duq.edu
Wei
Yunjing
Y
Liu
Wang
W
Zhang
Zhiyu
Z
D002412:Cations / Q000737:chemistry; D018360:Crystallography, X-Ray; D003500:Cyclization; D008094:Lithium / Q000737:chemistry; D008274:Magnesium / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D009570:Nitriles / Q000737:chemistry*; D013237:Stereoisomerism
D002412:Cations; D008670:Metals; D009570:Nitriles; D008094:Lithium; D008274:Magnesium