title: Metalated Nitriles: Stereodivergent Cation-Controlled Cyclizations1.
abstract: Stereodivergent cyclizations of gamma-hydroxy cyclohexanecarbonitriles are controlled simply through judicious choice of cation in the alkylmetal base. Deprotonating a series of cyclic gamma-hydroxy nitriles with i-PrMgBr generates C-magnesiated nitriles that cyclize under stereoelectronic control to cis-fused hydrindanes, decalins, and bicyclo [5.4.0] undecanes. An analogous deprotonation with BuLi triggers cyclization to trans-fused hydrindanes, decalins, and bicyclo [5.4.0] undecanes consistent with a sterically controlled electrophilic attack on an equatorial nitrile anion. Using cations to control the geometry of metalated nitriles provides a versatile, stereodivergent cyclization to cis- and trans-hydrindanes, decalins, and [5. 4. 0] undecanes, and reveals the key geometric requirements for intramolecular S(N)2 and S(N)2' displacements.
authors: Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282-1530, flemingf@duq.edu.
authors: Fraser F
authors: FF
authors: Fleming
authors: Yunjing
authors: Y
authors: Wei
authors: Wang
authors: W
authors: Liu
authors: Zhiyu
authors: Z
authors: Zhang