Unusual reactivity of isocyanates with dioxo- and diimidomolybdenum(VI) complexes
摘要:
Phenyl isocyanate reacts with dioxo- and diimidomolybdenum(VI) complexes such as Mo(O)2(mes)2 (1) (mes = mesityl = 2,4,6-C6H2Me3), Mo(mes)2CH2PBu3(O)2 (2), Mo(mes){CPBu3(mes)}(O)2(3) and Mo(NBu(t))2(mes)2 (4), selectively affording phenyl mesityl amide. This reaction proceeds via insertion into the Mo-mesityl bond, leading to an unstable oxazamolydenacycle which has been identified by C-13 NMR. This intermediate is probably hydrolysed with generation of the amide during chromatographic work-up.