SYNTHESIS AND H-1,C-13 AND P-31 NMR-STUDIES OF 2,10-DICHLORO-6-ARYLOXY-12H-DIBENZO[D,G][1,3,2]DIOXAPHOSPHOCIN 6-OXIDES

The spectral analyses and syntheses of several novel 2,10-dichloro-6-aryloxy/alkyl-12H-dibenzo[d,g] [1,3,2]dioxaphosphocin 6-oxides have been achieved. Long-range coupling [5J(H,P) = 2.4 Hz] was observed between phosphorus and the bridged methylene protons. Based upon NMR data, a tub-like conformation is proposed for the central eight-membered dioxaphosphocin ring. Long-range 2J(P,O,C) and 3J(P,O,C,C) couplins were determined, as were the P-31 chemical shifts for sixteen members of these, new heterocycles. A variable-temperature study of one member suggested the presence of a tub form as a reasonable candidate for one major conformer but the presence of other forms was also implied.