Reactions of 2‐(1,3‐Dithiolan‐2‐ylidene)malononitrile with Amino‐ and Hydrazinophosphorus Compounds: A Facile Route to Functionalized Phosphorus Heterocycles

Abstract

A facile and efficient route to functionalized phosphorus heterocycles was achieved by treatment of 2‐(1,3‐dithiolan‐2‐ylidene)malononitrile with amino‐ and hydrazinophosphorus compounds in the presence of a strong base via fragmentation of 1,3‐dithiolane ring.

Synthesis and Characterization of Some Novel Phosphorylated 4‐Oxo‐2‐phenylquinazolines

“…Next, compounds 1 and 2 reacted with equivalent amounts of phenylphosphonic dichloride in the presence of triethylamine in tetrahydrofuran. After adding water, the white solids, (4-oxo-2-phenylquinazolin-3(4H)-yl) phenyl phosphinic acid (11) and N-(4-oxo-2-phenylquinazolin-3(4H)-yl) phenyl phosphonamidic acid (12) were obtained, respectively. Furthermore, the latter compounds were also isolated in moderate yields through oxidation of compounds 7B and 8B, respectively, by aqueous hydrogen peroxide in tetrahydrofuran [18] (Scheme 3).…”

“…All the crude products were filtered off, washed with water, and crystallized from diluted ethanol. (2), 289 (20), 275 (100), 260 (34), 246 (14), 129 (2), 103 (2), 77 (11). Anal.…”

“…However, to the best of our knowledge, there are no reports available on the synthesis of 4‐oxo‐quinazolines by incorporating phosphine and aminophosphine units. With this background and also as a part of our ongoing research interest in the synthesis of phosphorus compounds containing bioactive heterocycles , we suggest a simple method for synthesis of 4‐oxo‐2‐phenyl‐quinazolines incorporates with phosphine, aminophosphine and their oxides, and some derived phosphorus acids. The method depends on treatment of 2‐phenylquinazolin‐4(3 H )‐one ( 1 ) and 3‐amino‐2‐phenyl‐quinazolin‐4(3 H )‐one ( 2 ) with some phenylphosphorus halides in different ratios in dry tetrahydrofuran.…”