Abstract
The catalyst assembled from inexpensive, air-stable RuHCl(CO)(PPh(3))(3,) JOSIPHOS (SL-J502-1), and NaI affects anti-diastereo- and enantioselective crotylation of alcohol proelectrophiles via hydrogen autotransfer. This operationally simple protocol bypasses use of iodide-bearing precatalyst RuI(η(3)-C(3)H(5))(CO)(3), which is not commercially available. Using this method, formal syntheses of cryptophycins 1-4 and 24 are achieved in a fraction of the steps previously required.