A dry, 250-ml., one-necked, round-bottomed flask equipped with a magnetic stirrer and a three-way stopcock is charged with 4 g. (0.05 mole) of ethyl nitrite (Note 1), 4 g. of dry tetrahydrofuran (Note 2), and 2.35 g. (0.0331 mole) of pyrrolidine (Note 3). The stopcock is closed (Note 4), and the mixture is stirred at room temperature for 2 days. Excess ethyl nitrite, tetrahydrofuran, and the ethanol formed are removed from the N-nitrosopyrrolidine (Note 5) by stirring at 25° under reduced pressure (10 mm., water aspirator, (Note 6) for 2 hours. The stopcock is fitted with a rubber septum, the air in the system is replaced with dry argon (Note 4) and (Note 7)), and 50 ml. of tetrahydrofuran is injected by syringe. A solution of lithium diisopropylamide is prepared in a separate, dry, 100-ml. flask by adding 21.1 ml. (0.0340 mole) of a 1.61 M solution of n-butyllithium in hexane (Note 8) to a solution of 3.44 g. (4.76 ml., 0.0341 mole) of diisopropylamine (Note 9) in 25 ml. of tetrahydrofuran at −78° (methanol–dry ice bath) with stirring under argon. The solution is warmed to 0° in 15 minutes, then added dropwise with a syringe within 4 minutes to the nitrosamine solution, stirred at −78°. Stirring of the yellow to orange solution is continued at this temperature for 25 minutes. A solution of 5.46 g. (0.0300 mole) of benzophenone in 12 ml. of tetrahydrofuran is added dropwise by syringe (Note 10), and the mixture is stirred for 12 hours at −78°, then warmed to 0° within 2 hours. After addition of 0.6 ml. (0.03 mole) of water, the flask is transferred from the argon line to a rotary evaporator (within the hood). Solvents and diisopropylamine are removed under reduced pressure in a 40° bath (Note 11). The remaining solid is dissolved with slight warming in 120 ml. of dry methanol (Note 12), before 3.9 g. (66 equivalents) of Raney nickel (Note 13) is rinsed into the solution with 30 ml. of dry methanol. The reaction vessel is equipped again with the three-way stopcock, and the air in the flask is replaced with hydrogen (Note 7). The flask is filled five times with hydrogen from a balloon; during this operation vigorous stirring of the Raney nickel–methanol suspension is necessary. The flask is attached to a mercury bubbler to maintain a positive hydrogen pressure (200 mm.) supplied from a cylinder, as shown in Figure 1. The reaction mixture is stirred for 3 hours at room temperature while a slow stream of hydrogen is passed through the system. The major part of the solution is decanted and filtered, and the remaining Raney-nickel suspension is extracted by refluxing three times for 10 minutes each with 20 ml. of methanol (Note 14). The combined methanol solutions are concentrated under reduced pressure. The residue is dissolved in 150 ml. of diethyl ether and 100 ml. of water, the layers are separated (Note 15), and the aqueous layer is extracted three times with 50-ml. portions of ether. The combined extracts are dried over sodium carbonate and concentrated in a rotary evaporator to a total volume of 150 ml. Dry hydrogen chloride gas is bubbled into the solution with stirring until the mixture is acidic, The almost colorless precipitate of the hydrochloride is filtered, washed two times with 30-ml. portions of dry ether, and dried in a desiccator under reduced pressure for 3 hours, giving 5.99–6.11 g. (58–60%, based on benzophenone) of the product, m.p. 244–249° (dec.). Recrystallization from methanol–acetone gives 5.06–5.20 g. (58–60%) of analytically pure product, m.p. 267–269° (dec.) (Note 16). The free base is obtained by treatment of the hydrochloride with 10% aqueous sodium hydroxide and extraction with ether, m.p. 82–83° (Note 17).