A Concise Total Synthesis of Pyrovellerolactone Using a Rhodium-Catalyzed [(3+2)+2] Carbocyclization Reaction

作者：Evans P Andrew^*; Ingle**y Phillip A; Kilbride Kathryn

来源：Organic Letters, 2013, 15(8): 1798-1801.

DOI：10.1021/ol400165x

A concise and highly convergent three-step total synthesis of the lactarane natural product, pyrovellerolactone, is described. The key step involves a regio- and diastereoselective Modiunnatalyzed [(3 + 2) + 2] carbocyclization of an alkenylidenecyclopropane with a 4-hydroxybut-2-ynoate followed by an in situ intramolecular lactonization to generate the tricyclic core in a single operation. This represents the first example of a higher-order [3 + 2 + 2] carbocyclization reaction in total synthesis, which is likely to provide an important strategy for the construction of related targets within this sesquiterpene family.

• 出版日期2013-4-19