Synthesis, antioxidant and antimicrobial activity of novel benzene-1,4-diamine-bis-dioxaphosphepine-6λ5 iminophosphoranes

A new class of novel benzene‐1,4‐diamine‐bis‐dioxaphosphepine‐6λ5 iminophosphoranes (5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j) were synthesized by the reaction of 6‐chlorodibenzo[d,f][1,3,2]dioxaphosphepine (2) with 1,4‐diaminobenzene to form bis‐dibenzo[d,f][1,3,2]dioxaphosphepin‐6‐yl‐benzene‐diamine (3). Its subsequent reaction with different alkyl/aryl azides (4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j) in tetrahydrofuran at 50–60°C under inert atmosphere yielded title compounds. Their structures were established by elemental analysis, IR, 1H, 13C, 31P NMR, and mass spectral studies. All the title compounds were screened for antioxidant properties and found to exhibit potent in vitro antioxidant and antimicrobial activity J. Heterocyclic Chem., (2010).