Stereochemical Studies of Chiral Nonconjugated Carbanions. Asymmetric Alkylation of Aldehydes with Sulfur-Substituted Carbanions of Chiral. ALPHA.-1, 3-Dithian-2 …
H Chikashita, T Yuasa, K Itoh
Index: Chikashita, Hidenori; Yuasa, Tsutomu; Itoh, Kazuyoshi Chemistry Letters, 1992 , # 8 p. 1457 - 1460
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Citation Number: 8
Abstract
A new type of asymmetric induction based on the nucleophilic addition of sulfur-substituted nonconjugated carbanions produced from a variety of chiral α-(1, 3-dithian-2-yl) acetals to achiral aldehydes was studied. The reaction with the carbanion of the chiral acetal derived from (4R, 5R)-3, 6-diethyl-3, 6-dimethoxy-4, 5-octanediol showed the best stereoselectivity (ds= 2.4: 1-6.3: 1) producing a chiral secondary-alcohol center.
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