Aldol strategy: coordination of the lithium cation with an alkoxy substituent

S Masamune, JW Ellingboe…

Index: Masamune, Saturu; Ellingboe, John W.; Choy, William Journal of the American Chemical Society, 1982 , vol. 104, # 20 p. 5526 - 5528

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Citation Number: 103

Abstract

4 (Scheme 11) with a Z (0)-enolate (5)'proceeds through a Cram-type2 transition state (6)[with 5 approaching 4 from the.(re) face of 41 or (7)[with 5 approaching 4 from the p (si) face of 41.'Transition states 6 and 7 should provide the 2, 3-syn, 3, 4-anti, 4, 5-syn-3, 5- dihydroxy-2, 4-dimethylcar~ nyl derivative 8 and the corresponding 2, 3-syn, 3, 4-syn, 4, 5- syn derivative 9,'respectively. As the lithium cation coordinates more tightly with both ...