The use of tetraethyl vinylidenebisphosphonate as a dipolarophile in 1,3-dipolar
cycloaddition reactions was investigated. In particular, the cycloaddition reactions
between tetraethyl vinylidenebisphosphonate and azides and nitrile oxides, and of
tetraethyl vinylidenebisphosphonate in the Grigg azomethine 1,3-dipolar cyclization
were studied, affording highly functionalized five-membered rings containing the bisphosphonic
unit. These straightforward methods allow the preparation of diverse and fairly complex
structures bearing the bisphosphonate moiety, which belong to a group of pharmacologically
important compounds.
Key words
bisphosphonates - 1,3-dipolar cycloadditions - azides - nitrile oxides - Grigg azomethine
ylides