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Organo-manganese ?2-auxiliary directed reactions: a diastereoselective approach to 2,3-allenols.

ABSTRACT: Propargyl aldehydes underwent isomerization to allenyl aldehydes under mildly basic conditions when complexed to an organo-manganese auxiliary using methylcyclopentadienyl manganese tricarbonyl (MMT). This traceless auxiliary magnifies the axial chirality of the allene moiety, allowing for highly diastereoselective additions to the aldehyde carbonyl and subsequent access to an array of 2,3-allenols. Using this strategy, a nitrile-substituted 2,3-allenol was prepared and efficiently converted to Hagen's gland lactone.

SUBMITTER: Roy A

PROVIDER: S-EPMC4537065 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Organo-manganese η2-auxiliary directed reactions: a diastereoselective approach to 2,3-allenols.

Roy Animesh A Bhat Bilal A BA Lepore Salvatore D SD

Organic letters 20150209 4

Propargyl aldehydes underwent isomerization to allenyl aldehydes under mildly basic conditions when complexed to an organo-manganese auxiliary using methylcyclopentadienyl manganese tricarbonyl (MMT). This traceless auxiliary magnifies the axial chirality of the allene moiety, allowing for highly diastereoselective additions to the aldehyde carbonyl and subsequent access to an array of 2,3-allenols. Using this strategy, a nitrile-substituted 2,3-allenol was prepared and efficiently converted to ...[more]

PMID: 25662282

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