NiO2 in pentane T=20°C;

NiO2; ammonia in diethyl ether T=-20°C; 4 h;

1: pyridine / diethyl ether 2: 1.) Ti(O-i-Pr)4, i-PrMgBr; 2.) aq. 1 N HCl / 1.) ether, -78 deg C to -50 deg C, 0.5 h, -50 deg C to -40 deg C, 1.5 h; 2.) ether, -40 deg C to RT, 0.5-1 h View Scheme