Abstract
2-Benzylidenecyanomethyl-1,3-benzothiazole (1) reacts with trialkyl phosphites (6) to give a mixture of the corresponding-phosphonates 9 (E & Z) with 6a, b or 16c (E & Z) with 6c (∼50%) and -[2,1-b]-fused pyrido-derivative 12 (∼20%), meanwhile, with dialkyl phosphonates 7 affords only the phosphonates 16 (E & Z) in high yields (∼80%). Only E-isomer of both types of phosphonates could be isolated in a pure form. α-Benzil monoxime (22) reacts with 6 to give oxazaphospholes 23, and with 7 to give α-hydroxyamino phosphonates 25.