Tetraethyl vinylidenebisphosphonate. A versatile synthon for the preparation of bisphosphonates

RODRIGUEZ, JUAN BAUTISTA

SYNTHESIS-STUTTGART

GEORG THIEME VERLAG KG

Lugar: Stuttgart; Año: 2014 vol. 46 p. 1129 - 1142

0039-7881

Tetraethyl vinylidenebisphosphonate (1) is a versatile synthetic intermediate that allows access to a variety of highly functionalized compounds bearing the bisphosphonic moiety. As an electron-deficient alkene, this compound is able to undergo conjugate addition with a variety of reagents including strong nucleophiles such as organometallic reagents, enolates as well as very mild nucleophiles such as amines, mercaptans, alcohols, etc. Compound 1 also possesses the ability to behave as a dipolarophile or dienophile in 1,3-dipolar cycloaddition or Diels-Alder reactions giving rise to five- or six-membered rings containing the bisphosphonic unit. In summary, compound 1 is a very useful synthon to have at hand straightforward syntheses of bisphosphonate derivatives of diverse structures. This bisphosphonate moiety has proven to be very important to put forth important pharmacological action.