Benzhydrylamine → HCID 10729452, compound

Participants

Reaction Steps

A 100-mL round-bottomed flask containing a stir bar was charged with Na2SO4 (8.0 g) and CH2Cl2 (40 mL). Trimethylacetaldehyde (8) (7.65 mL, 52 mmol, 1.3 equiv) and aminodiphenylmethane (9) (6.89 mL, 40 mmol, 1.0 equiv) were added sequentially via syringe while stirring. The flask was capped with a plastic stopper, and the mixture was stirred at room temperature. The mixture became cloudy after 5 min. After stirring for 1 h, the solution was decanted into a 200-mL round-bottomed flask, rinsing with CH2Cl2 (4×5 mL) and concentrated to 8-10 mL using a rotary evaporator. The flask was then maintained at 1 torr for 10 min. A 5-cm diameter fritted disk funnel was filled with a 2-cm high layer of silica gel. The funnel was rinsed with a solution of 20:1:0.5 hexanes/Et2O/triethylamine (50 mL) under reduced pressure, followed by a solution of 20:1 hexanes/Et2O (50 mL). The oil prepared above was dissolved in 20:1 hexanes/Et2O (25 mL) and rinsed through the frit into a tared 250-mL round-bottomed flask under reduced pressure, rinsing with 20:1 hexanes/Et2O (4×25 mL). The mixture was concentrated (30 torr→1 torr) to provide a clear, pale yellow oil that solidified into a white solid. The solid was broken up into approximately 1-cm diameter pieces using a spatula, and was maintained at 1 torr for another 15 min to provide N-(2,2-dimethyl propylidene)diphenylmethanamine (2a) as a white solid in approximately 98% 1H-NMR purity. The product was used in the next step without further purification. Yield: 9.93 g (39.6 mmol, 99%).

Provenance & Evidence