in dichloromethane T=0°C;

1: SOCl2 / Heating 2: benzene / 3 h / 0 deg C to RT View Scheme

Schwartz's reagent in tetrahydrofuran T=20°C; 1.5 h; Inert atmosphere;

1: N,N-di-isopropyl-2-methoxybenzamide With tert.-butyl lithium in tetrahydrofuran; hexane T=-78°C; 2.5 h; Inert atmosphere; 2: boric acid trimethyl ester in tetrahydrofuran; hexane T=-78 - 25°C; Inert atmosphere;