N,N,N',N',N'',N''-hexamethylphosphoric triamide; magnesium 1 h; Heating;

T=200°C; 3.5 h;

1: 1.) methylene blue, O2; 2.) sodium borohydride / 1.) methanol, irradiation, 3 h; 2.) 12 h, water 2: 78.5 percent / phenyl isocyanate / CHCl3 / 12 h / Heating View Scheme