Abstract
A simple method for design of some novel 1,2-benzoxaphosphinines 2–9, was achieved. The methodology depended on cyclization of 1-(2-hydroxy-phenyl)-3-phenylpropane-1,3-dione (1) as starting material with some phosphorus halides in dry solvent in the presence of a base. Reaction of the substrate 1 with some phosphorus halides, such as P,P-dichlorophenylphosphine, phenyl phosphonic dichloride, phenyl phosphorodichloridate, and phosphorus oxychloride in dry toluene containing triethylamine led to a predominant formation of 3-benzoyl-4-hydroxy-2H-1,2-benzoxaphosphinines 2–5, respectively. Under the same reaction conditions, the molecular structures of type 3-benzoyl-4H-1,2-benzoxaphosphinin-4-ones 6 and 7 were isolated by treatment of the substrate 1 with phosphorus pentachloride and phosphorus tribromide, respectively. In addition, the interesting 4-(1-phenyl-ethanoyl)-1,2,λ5-benzoxaphosphinines 8 and 9 were obtained by treatment of compound 1 with acetonyl and benzyl triphenylphosphonium chlorides, respectively, in dry dioxane and sodium hydride. The chemical structures of the title compounds were established by elemental analysis and spectral tools.
Graphical Abstract
Acknowledgments
The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through large research groups program under grant number RGP.2/8/43.