A facile synthesis and spectral (ir,1H,13C,31P nmr) studies of 2,10-dichloro-6-aryloxy-12H-dibenzo[d,g][1,3,2]dioxaphosphocin 6-sulfides

Abstract

The synthesis of new 2,10-dichloro-6-aryloxy-12H-dibenzo[d,g][1,3,2]dioxaphosphocin 6-sulfides 4 was achieved in two steps with high yields from the simple materials 5,5′-dichloro-2,2′-dihydroxydiphenyl-methane (1) and thiophosphoryl chloride (2) which produced the key intermediate 2,6,10-trichloro-12H-dibenzo[d,g][1,3,2]dioxaphosphocin 6-sulfide (3). Treatment of 3 with substituted phenols under phase transfer catalytic (PTC) conditions led to members of 4. Long range coupling [5J(P,H) = 3.6 Hz] was observed between phosphorus and one of the bridged methylene protons in 4. A 13C nmr analysis revealed 2J(P,O,C), 3J(P,O,C) 4J(P,O,C) and 5J(P,O,C) couplings. All 31P nmr chemical shifts for thirteen members of these new heterocycles are reported for the first time. The nmr data are not totally definitive to confirm a boat-chair as the major conformer for the central eight-membered dioxaphosphocin ring, but such a conformer is tentatively suggested as favored.