ChemInform Abstract: Synthesis of Novel Functionalized gem‐Bisphosphonates.

Abstract

Synthesis of Novel Functionalized gem-Bisphosphonates.-Michael-type addition of the masked polyfunctional nucleophiles (II) to tetraethyl ethylidenebisphosphonate (I) produces the gem-bisphosphonates (III). The compounds (IIIb) and (IIId) are deprotected yielding the primary amines (IV). The carboxylic acid (V) is obtained by ester saponification of (IIIa) followed by thermal decarboxylation of the dicarboxylic acid formed. Reaction of potassium cyanide (VI) with (I) gives 3,3-bis(diethoxyphosphoryl)propionitrile (VII). The compounds (III) -(V), and (VII) are potentially useful in the therapy of bone tissues. -(STURTZ, G.; GUERVENOU, J.; Synthesis (1991) 8, 661-662; Lab. Chim. Heteroorg., UFR Sci. Techn., 29287 Brest, Fr.; EN)

Organocatalytic Enantioselective Epoxidation of Some Aryl-Substituted Vinylidenebisphosphonate Esters: On the Way to Chiral Anti-Osteoporosis Drugs

“…Since the synthesized epoxides have a significant electrophilic character at the C-2 position, they could, in principle, react with a wide range of nucleophiles [35,36]. Hence, the epoxides obtained in their racemic form were tested towards sulfur-containing nucleophiles and organometals.…”

Organocatalytic Stereoselective Epoxidation of Aryl-Substituted Vinylidenebisphosphonate Esters: On the Way to Chiral Anti-Osteoporosis Drugs

“…Since the synthesized epoxides have a significant electrophilic character at the C-2 position, they could, in principle, react with a wide range of nucleophiles [35,36]. Hence, the epoxides obtained in their racemic form were tested towards sulfur-containing nucleophiles and organometals.…”

Synthesis, spectroscopic, and structural characterization of new functionalized gem-bisphosphonate complexes of tin(IV) chloride

“…The ligands tetraethyl 2-cyano-ethylidene-1,1-bisphosphonate (1b) and tetraethyl 2-benzylaminoethylidene-1,1-bisphosphonate (1c) were synthesized from the reaction of 1a with potassium cyanide in aqueous ethanol [24], or with benzylamine in anhydrous DCM [25], respectively as described previously…”