Synthesis and Characterization of 6-(1,3-dimethylureido) dibenzo[c,e][1,2]oxaphosphinine 6-oxide

The compound 6-(1,3-dimethylureido)dibenzo[c,e][1,2]oxaphosphinine 6-oxide was synthesized in a single step, under mild reaction conditions, from the commercially available H-phosphinate 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and 1,3-dimethylurea in the presence of a mild oxidant and triethylamine. The reaction led to the formation of a P–N bond between the phosphoryl group and one of the urea nitrogen atoms. The compound was spectroscopically characterized, and thermal properties were investigated.