The Journal of organic chemistry

Synthesis of γ, δ-Unsaturated-β-keto Lactones via Sequential Cross Metathesis-Lactonization: A Facile Entry to Macrolide Antibiotic (-)-A26771B

J Gebauer, S Blechert

Index: Gebauer, Julian; Blechert, Siegfried Journal of Organic Chemistry, 2006 , vol. 71, # 5 p. 2021 - 2025

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Citation Number: 33

Abstract

The intramolecular trapping of hydroxyalkylketenes derived from substrates such as 3 is quite sensitive to transition-state conformational effects manifested by ring size. 5 Whereas the preparation of saturated eight-membered β-keto lactones worked well, 2b the cyclization to corresponding 10- and 11-membered analogues failed even under high dilution conditions (<10 - 4 M). 2a For this reason and with respect to the additional unsaturation in the starting material ...