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1,2-Dihydropentalenes from fulvenes by [6 + 2] cycloadditions with 1-isopropenylpyrrolidine.

ABSTRACT: In situ generated acetone pyrrolidine enamine undergoes [6 + 2] cycloadditions with fulvenes to give 1,2-dihydropentalenes. This ring annulation method works particularly well with 6-monosubstituted fulvenes and is subject to steric hindrance at C-6 of the fulvene. On the basis of mechanistic studies, optimal conditions have been developed for a one-pot synthesis of 1,2-dihydropentalenes using catalytic amounts of pyrrolidine.

SUBMITTER: Coskun N

PROVIDER: S-EPMC3295583 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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1,2-Dihydropentalenes from fulvenes by [6 + 2] cycloadditions with 1-isopropenylpyrrolidine.

Coşkun Necdet N Ma Jingxiang J Azimi Saeed S Gärtner Christian C Erden Ihsan I

Organic letters 20111026 22

In situ generated acetone pyrrolidine enamine undergoes [6 + 2] cycloadditions with fulvenes to give 1,2-dihydropentalenes. This ring annulation method works particularly well with 6-monosubstituted fulvenes and is subject to steric hindrance at C-6 of the fulvene. On the basis of mechanistic studies, optimal conditions have been developed for a one-pot synthesis of 1,2-dihydropentalenes using catalytic amounts of pyrrolidine. ...[more]

PMID: 22029269

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