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Asymmetric alkylation of carboxyamides by using trans-2,5-disubstituted pyrrolidines as chiral auxiliaries

✍ Scribed by Yasuhiro Kawanami; Yoshio Ito; Toshiyuki Kitagawa; Yoshiyuki Taniguchi; Tsutomu Katsuki; Masaru Yamaguchi

Publisher: Elsevier Science
Year: 1984
Tongue: French
Weight: 281 KB
Volume: 25
Category: Article
ISSN: 0040-4039
DOI: 10.1016/s0040-4039(01)80046-0

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✦ Synopsis

Sumnary: trans-2,5-Bis(methoxymethyl)-and trans-2,5-bis(methoxymethoxymethy1)pyrrolidines proved to be excellent chiral auxiliaries for the asymmetric alkylation of the corresponding carboxyamide enolates giving good chemical yield and high stereoselectivity (invariably over 95% de), with remarkable flexibility to substrates and reaction conditions.

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