Synthesis of Novel 4-(1,3,2-Diazaphosphinin-5-yl)-1,2-Dihydrothieno[3,2-d][1,2,3] Diazaphosphinines: Cyclization of 5-[(2-Thienyl)Methyl]Hydrazono-2-Oxido-2-Phenyl-4-(Trifluoromethyl)-1H-1,3,2-Diazaphosphinine with Phosphorus Halides

Abstract

Synthesis of novel 4-(1,3,2-diazaphosphinin-5-yl)-1,2-dihydrothieno[3,2-d][1,2,3] diazaphosphinines 5-8 was achieved. The methodology depended on preparation of 5-[(2-thienyl)methyl]hydrazono-2-oxido-2-phenyl-4-(trifluoromethyl)-1H-1,3,2-diazaphosphinine (4) through the cyclization of 2-[(dimethylamino)methylene]-4,4,4-trifluoro-1-(2-thienyl)-butane-1,3-dione (2) with phenyl phosphonic diamide, followed by hydrazine hydrate. Cyclization of the hydrazone 4 with some phosphorus halides at refluxing pyridine gave the target products in acceptable yields.

Graphical Abstract

Keywords:

• 1,2,3-Diazaphosphinine
• 1,3,2-diazaphosphinine
• thiophene
• phosphorus halides

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through research groups project under grant number (RGP.2/2/42).