Macrocyclization by nickel-catalyzed, ester-promoted, epoxide-alkyne reductive coupling: total synthesis of (-)-gloeosporone.

Ringing the changes: The total synthesis of the title compound centers around a novel strategy that employs a nickel(0)-phosphine complex and triethyl borane in an efficient closure of a 14-membered ring through C--C bond formation (see scheme; cod=cyclooctadiene). The synthesis was accomplished in 10 steps and in approximately 9 % overall yield.