The use of boronic ester chemistry in the construction of synthetic intermediates containing two or three chiral centers corresponding to steric relationships in the macrolide leuconolide has been explored. A four-carbon chain with a substituent at each carbon has been built from each end, and the effects of different chiral directors and masking groups have been compared. Exceptionally facile debenzylation of a benzyloxy group separated by four carbon atoms from a boronic ester function has been observed and may account for the failure of earlier attempts to synthesize sugars via analogous chemistry. A novel method of reducing α-chloro boronic esters to alkylboronic esters with sodium hydride in DMSO has been found.

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