Surface-Mediated Hydrohalogenation of Isoprene: A Facile Preparation of Prenyl Halides

Abstract

The reaction of isoprene with SOCl₂ (0.5 mol equiv.) or PBr₃ (0.4 mol equiv.) or PI₃ (0.4 mol equiv.) in the presence of SiO₂ at −10°C produced prenyl chloride (82%), or bromide (70%) or iodide (65%), respectively, in less than 30 min reaction time.

Keywords:

• Silica gel
• Prenyl
• Hydrohalogenation

Acknowledgments

AMS thanks CNPq for a fellowship. We thank Gabriela F. Mendonça, Francesco Spano, and Milton R. Salles for preparation of PI₃. We also thank W. Bruce Kover and Joel Jones Jr. for helpful discussions.