BISPHOSPHONIC COMPOUNDS .3. PREPARATION AND IDENTIFICATION OF TETRAALKYL METHYLENEBISPHOSPHONATES AND (ALPHA-HALOMETHYLENE)BISPHOSPHONATES BY MASS-SPECTROMETRY, NMR-SPECTROSCOPY AND X-RAY CRYSTALLOGRAPHY

The preparation and identification of tetraalkyl methylenebisphosphonates {XYC[P(O)(OR)2]2; X = Y = H, Cl or Br and R = alkyl} have been studied. Detailed procedures are given for the synthesis of XYC[P(O)(OR)2]2 (X = Y = H; R = hexyl; X = Y = Cl or Br and R = Me). H-1, C-13 and P-31 NMR data are reported including 1J(CH), 2J(CP), 3J(CP) and 2J(PP) coupling constants. The fragmentation of 19 XYC[P(O)(OR)2]2 has been studied in the gas phase. The solid state structures are given for two compounds (X = Y = Cl, R = Pr(i) and X = Y = Br, R = Me).