Synthesis of a [(14) C]-steroid intermediate: an application of a nonstabilized Horner-Wadsworth-Emmons olefination approach.

Radiolabeled steroid derivative 1 was successfully prepared using a Horner-Wadsworth-Emmons approach: a [(14) C]-label was efficiently incorporated into the C-18 position of the molecule. Previously published procedures employing other olefination methods are either not applicable due to unavailability of [(14) C]-precursors or suffer from poor reactivity.