A New Synthesis of Key Intermediates for the Preparation of 5,6‐DiHETE and Lipoxin A4

The highly diastereoselective osmylation of a C  C bond in proximity to a complex fragment is the key step in the formation of 2 from the butadiene(tricarbonyl)iron complex 1. The diols 2 can be transformed readily into 3, key intermediates in the synthesis of 5,6-DiHETE and lipoxin A4. R  SiPh2tBu; R′  Me; E  CO2Me.