During the synthesis of a Cathepsin S inhibitor workers at Boehringer Ingelheim had problems converting the alcohol shown above to the phosphonate. Conversion of the alcohol to a chloride followed by traditional Michaelis-Arbusov reaction was unsatisfactory as the chloride was unstable. So a modified procedure was developed where the alcohol was treated with (EtO)₂PCl in toluene to presumably form the phosphite which then undergoes the Arbusov rearrangement to form the phosphonate. This is then reacted with aldehyde (7) to give the diene (11) in 75% overall yield.

J.C. Lorenz,* C.A. Busacca,* X. Feng, N. Grinberg, N. Haddad, J. Johnson, S. Kapadia, H. Lee, A. Saha, M. Sarvestani, E.M. Spinelli, R. Varsolan, X. Wei, X. Zeng, and C. Senanayake (Boehringer Ingelheim), J. Org. Chem., 2010, 75, 1155-1161.