Studies on phosphoroheterocycle chemistry I: A facile synthesis of new tricyclic phosphoroheterocycles 1,3,2-oxazaphospholidino(or oxazaphosphorino)[3,2-a][1,3,2]benzodiazaphosphorines

Reaction procedures have been developed for the preparation of structurally different phosphoroheterocyclic compounds. Firstly, the treatment of PCl3 with functionalized compound N-ethyl-2-(beta -hydroxyethyl)aminobenzamide g ave chlorinated phosphoroheterocycle, 1-(2-chloroethyl)-3-ethyl-2,3-dihydro -1,3,2-benzodiazaphosphorin-4(1H)-one 2-oxide. Secondly, novel tricyclic ph osphorobeterocycles, 1,3,2-oxazaphospholidino(or oxazaphosphorino)[3,2-a][1 ,3,2]benzodiazaphosphorines, have been conveniently synthesized by cyclizat ion of tris(diethylamino)phosphine with 2-(N-(beta or gamma -hydroxyalkyl)a minobenzamides. Finally. the reaction of 2-(N-ethoxycarbonylmethyl)amino-N- (2'-hydroxyethyl) benzamide with P(NEt2)(3) afforded five-membered phosphor oheterocycle, 3 -(2'-N-ethoxycarbonylmethylamino) benzoyl-2-diethylamino-1, 3,2-oxazaphospholidine-2-sulfide. Additionally, the preliminary bioassays s howed that several title compounds possessed herbicidal activity to some ex tent.