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2-azapinanes: aza analogues of the enantiomeric pinyl carbocation intermediates in pinene biosynthesis.

ABSTRACT: The enantiomeric 2-azapinanes, aza analogues of the pinyl carbocation intermediates in pinene biosynthesis, were synthesized from (-)- and (+)-cis-pinonic acids. The individual reactions in the 5-step sequence were Beckmann rearrangement of the pinonic acid oximes, cyclization to the N-acetyl lactams, hydrolysis to the NH-lactams, N-methylations, and LiAlH(4) reductions. The anti stereochemistry of the N-methyl groups in the salts with respect to the gem-dimethyl bridge was established by NOE measurements and by X-ray diffraction analysis.

SUBMITTER: Faraldos JA

PROVIDER: S-EPMC3415958 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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2-azapinanes: aza analogues of the enantiomeric pinyl carbocation intermediates in pinene biosynthesis.

Faraldos Juan A JA Kariuki Benson M BM Coates Robert M RM

Organic letters 20110124 5

The enantiomeric 2-azapinanes, aza analogues of the pinyl carbocation intermediates in pinene biosynthesis, were synthesized from (-)- and (+)-cis-pinonic acids. The individual reactions in the 5-step sequence were Beckmann rearrangement of the pinonic acid oximes, cyclization to the N-acetyl lactams, hydrolysis to the NH-lactams, N-methylations, and LiAlH(4) reductions. The anti stereochemistry of the N-methyl groups in the salts with respect to the gem-dimethyl bridge was established by NOE me ...[more]

PMID: 21261271

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