Lithium Bromide

Experimental procedure: An electrochemical cell with magnesium as the anode and galvanized steel wire as the cathode is added to a substrate (0.1 mmol, 1.0 eq.), 1,3-dimethylurea (0.3 mmol, 3.0 eq), tripyrrolidinophosphine oxide (1.0 mmol, 10 eq.), and 1.5 mol/L THF solution of LiBr (500 µL). The reaction mixture is added to THF (3 mL) and is purged with argon. Electrolysis is initiated at a cell ampere of 10 mA at room temperature. After full consumption of substrate, the cell is washed with diethyl ether, and solvent is removed in vacuo. To residue solution is added diethyl ether and solution of Rochelle salt, and then is stirred until two clear layers formed. The organic layer is separated, and the aqueous layer is extracted twice with diethyl ether. The combined organic layers are dried over anhydrous MgSO4. After the organics removed in vacuo, the residue is purified by short silica colum (elution: ethyl acetate) to give product.