Abstract:The dehydrogenative a-phosphonation of substituted N,N-dialkylanilines by dialkyl H-phosphonates was achieved under mild conditions by using environmentally benign iron(II) chloride as catalyst and tert-butyl hydroperoxide as oxidant. The reaction proceeded in the presence of electron-donating (methoxy, methyl, benzyl) and electron-withdrawing ring-substitutents (bromo, carbonyl, carboxyl, m-nitro) in moderate to good yields. The X-ray crystal structure of N-(5,5-dimethyl-2-oxo-2l 5 -[1,3,2]dioxaphosphinan-2-yl-methyl)-N-methyl-p-toluidine was determined. Bis-(4-(dimethylamino)phenyl)methane and bis-4,4'-(dimethylamino)benzophenone underwent bisphosphonation selectively by respective monophosphonation at the remote dimethylamino groups. Furthermore, the use of excess di-