disodium hydrogenphosphate; sodium amalgam in various solvent(s) 25 h; Ambient temperature;

1: 86 percent / Pyridine / diethyl ether / 4 h / 1 - 3 °C 2: 88 percent / dimethylformamide / 3 h / 55 - 60 °C 3: 1.) Sodium hydride / DMF 1.) r.t., 1.5 h, 2.) 30 h 4: 73 percent / Na/Hg, Na2HPO4 / various solvent(s) / 25 h / Ambient temperature View Scheme

1: 1.) Sodium hydride / DMF 1.) r.t., 1.5 h, 2.) 30 h 2: 73 percent / Na/Hg, Na2HPO4 / various solvent(s) / 25 h / Ambient temperature View Scheme

1: 88 percent / dimethylformamide / 3 h / 55 - 60 °C 2: 1.) Sodium hydride / DMF 1.) r.t., 1.5 h, 2.) 30 h 3: 73 percent / Na/Hg, Na2HPO4 / various solvent(s) / 25 h / Ambient temperature View Scheme

1: 1.) Sodium hydride / DMF 1.) r.t., 1.5 h, 2.) 30 h 2: 73 percent / Na/Hg, Na2HPO4 / various solvent(s) / 25 h / Ambient temperature View Scheme

T=185 - 190°C; 8 h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;