New Silicon-Mediated, Sequential Ring Expansions of n-Sized 2-Cycloalkenones into Hydroxyolefinic n+ m+ p Medium-Sized Lactones: Short Synthesis of (-)- …

GH Posner, MA Hatcher, WA Maio

Index: Posner, Gary H.; Hatcher, Mark A.; Maio, William A. Organic Letters, 2005 , vol. 7, # 19 p. 4301 - 4303

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Citation Number: 22

Abstract

In only four steps from 2-cyclopentenone and 2-cyclohexenone, sequential three-or four- atom and then one-to three-atom ring enlargements produce nine-to 12-membered hydroxyolefinic lactones on a gram scale. 2-Cyclopentenone undergoes this serial 5+ 3+ 2 process to form 10-membered ring natural (-)-phoracantholide-J in six linear steps and 26% overall yield.