Abstract:
The reaction of 2-tert-butoxy-5,6-benzo-1,3,2-dioxaphosphorin-4-one with hexafluoroacetone involves ring expansion to give a 6,7-benzo-1,3,2-dioxaphosphepine with partial preservation of the tert-butoxy substituent on the phosphorus atom. The product was heated in ether in the presence of triethylamine to obtain triethylammonium 4,4-bis(trifluoromethyl)-2,5-dioxo-6,7-benzo-1,3,2λ 5-dioxaphosphepin-2-olate. The steric structure of this compound was studied. © 2000 MAIK "Nauka/Interperiodica".