Oxidative Heterocoupling of Lithium Acylate α-Carbanions by the Action of 1,2-Dibromoethane

• Published in: Russian journal of organic chemistry 2023-09, Vol.59 (9), p.1482-1488
• Main Authors: Zorin, A. V., Zaynashev, A. T., Zorin, V. V.
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Lithium; Organic Chemistry
• ISSN: 1070-4280; 1608-3393
• DOI: 10.1134/S107042802309004X

Pairs of α-carbanions generated from lithium 2-methylpropanoate, butanoate, pentanoate, hexanoate, heptanoate, and phenylacetate by the action of lithium diisopropylamide on the corresponding acids (AH, BH) in THF reacted with 1,2-dibromoethane to give mixtures of oxidative homo- (2,2,3,3-tetramethyl-, 2,3-diethyl-, 2,3-dipropyl-, 2,3-dibutyl-, 2,3-dipentyl-, and 2,3-diphenylbutanedioic acids) and heterocoupling products (3-ethyl-2,2-dimethyl-, 2-ethyl-3-propyl-, 2-butyl-3-ethyl-, 2-ethyl-3-pentyl-, 2-ethyl-3-phenyl-, 2-butyl-3-propyl-, 2-pentyl-3-propyl-, 2-phenyl-2-propyl-, 2-butyl-3-pentyl-, 2-butyl-3-phenyl-, and 2-pentyl-3-phenyl­butanedioic acids) in overall yields of 83–99%. The ratio of the homo- and heterocoupling products depended on the structure of the initial α-carbanions.