Tetrahedron letters

Dimethylaluminum methyltellurate, a new reagent for the cleavage of hindered methyl esters under exceptionally mild conditions by a novel mechanism

BVS Reddy, LR Reddy, EJ Corey

Index: Reddy, B.V. Subba; Reddy, Leleti Rajender; Corey Tetrahedron Letters, 2005 , vol. 46, # 27 p. 4589 - 4593

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Citation Number: 16

Abstract

In the course of recent investigations on the total synthesis of the potent proteasome inhibitor salinosporamide A (1) 1 and related structures we encountered great difficulty in the hydrolysis of the hindered methyl ester function in a late intermediate (2). 2 and 3 Because of the combination of strong steric shielding of the COOMe carbonyl in 2 and the ease of decomposition by retroaldol pathways, the conversion of methyl ester 2, for example, R = i-Pr, into the corresponding ...