Bisphosphonic compounds. Part 3. Preparation and identification of tetraalkyl methylene- and (α-halomethylene)bisphosphonates by mass spectrometry, NMR spectroscopy and X-ray crystallography

Abstract

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). ¹H, ¹³C and ³¹P 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 = Prⁱ and X = Y = Br, R = Me).