Consequences of Acid Catalysis in Concurrent Ring Opening and Halogenation of Spiroketals<sup>1</sup>
作者:Thomas G. LaCour、Zhiwei Tong、Philip L. Fuchs
DOI:10.1021/ol991078r
日期:1999.12.1
[formula: see text] Lewis and/or Bronsted acid additives permit ringopening and halogenation of spiroketals at substantially reduced temperatures to produce omega-iodo enol ethers in improved yield and purity, which can undergo further reaction in the presence of distal electrophilic centers to give new steroid skeletons.