Efficient Microscale Preparation of Isotopically Enriched 1‐[⁷⁹Br]Bromo‐2‐Fluoroethylene, [⁷⁹Br]BrHC˭CHF

Abstract

An efficient preparation of 1‐[⁷⁹Br]bromo‐2‐fluoroethylene, [⁷⁹Br]BrHC˭CHF, was carried out by a three‐step procedure: (a) natural 1‐bromo‐2‐fluoroethylene, BrHC˭CHF, was iodinated to 1‐fluoro‐2‐iodoethylene, FHC˭CHI; (b) 1‐fluoro‐2‐iodoethylene was ⁷⁹Br₂‐brominated to 1,2‐di[⁷⁹Br]bromo‐1‐fluoro‐2‐iodoethane, [⁷⁹Br]BrFCHCH[⁷⁹Br]BrI; and (c) 1,2‐di[⁷⁹Br]bromo‐1‐fluoro‐2‐iodoethane was dehalogenated to 1‐[⁷⁹Br]bromo‐2‐fluoroethylene, [⁷⁹Br]BrHC˭CHF. The yield of isolated product, on a 2‐mmol scale, was 62% with respect to ⁷⁹Br₂.

Keywords:

• 1‐[⁷⁹Br]Bromo‐2‐fluoroethylene
• 1‐bromo‐2‐fluoroethene
• fluoroalkenes
• infrared spectroscopy
• isotopic labeling
• reductive dehalogenation

Acknowledgments

The authors thank Lucio Ronchin and Francesco Pinna (Dipartimento di Chimica, Università Ca' Foscari di Venezia) for their help with GC and Maurizio Selva (Dipartimento di Scienze Ambientali, Università Ca' Foscari di Venezia) for his help with GC/MS spectra. Daniela Baldan is also acknowledged for her valuable aid in the article preparation.