Stereochemistry of carbanion reactions at sp3-carbon

Katsuhiko Tomooka, Tatsuya Igarashi

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The stereochemistry (inversion vs. retention) of reactions at sp3-carbanion centers is one of the pressing problems in organic chemistry. This review describes our recent studies on the stereochemistry of carbanion reactions using enantiomerically defined α-(alkoxy) organolithiums generated from the enantio-enriched stannanes via Sn/Li exchange: (1) A new practical method for asymmetric synthesis of α-hydroxystannanes is described. (2) The [2, 3]-Wittig rearrangement was shown to proceed with complete inversion of configuration at the Li-bearing migrating terminus. (3) The carbolithiative cyclization is proved to proceed with complete retention of configuration at the Li-bearing carbon. (4) The [1, 2]-Wittig rearrangement is shown to proceed predominantly with inversion of configuration at the Li-bearing terminus and retention at the migrating center, wherein a significant level of mutual enantiomer recognition is observed in the radical recombination process.

Original languageEnglish
Pages (from-to)480-486
Number of pages7
JournalYuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry
Volume53
Issue number6
DOIs
Publication statusPublished - Jan 1 1995
Externally publishedYes

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Bearings (structural)
Stereochemistry
Carbon
Enantiomers
Cyclization

All Science Journal Classification (ASJC) codes

  • Organic Chemistry

Cite this

Stereochemistry of carbanion reactions at sp3-carbon. / Tomooka, Katsuhiko; Igarashi, Tatsuya.

In: Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry, Vol. 53, No. 6, 01.01.1995, p. 480-486.

Research output: Contribution to journalArticle

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