6H-DIBENZ[c,e][1,2]OXAPHOSPHORINS: SYNTHESIS AND CHEMISTRY

The reaction of 1-phenylphenol with phosphorus trichloride at elevated temperature using zinc chloride as a catalyst gave the 6H-dibenz[c,e][1,2]oxaphosphorin 1. The reaction of 1 with the phenols 3a–e gave the corresponding 6-phenoxy derivatives 4a–e. In the case of the sterically hindered phenol 3e, an improved procedure involved the reaction of the sodium phenolate of 3e with 1. The reaction of the benzenethiols 5a–b with 1 using triethylamine as an acid acceptor gave the corresponding derivatives 6a–b.