m-Toluidine → 3-methyl-N-(1-o-tolylethyl)aniline

To a flame-dried 100 mL round-bottom flask equipped with a magnetic stirring bar was added 260 mg of decaborane (260 mg, 2.1 mmol), dry methanol (52 mL), m-toluidine (780 μL, d=0.989 g/mL, 7.2 mmol), and 2′-methylacetophenone (1 mL, d=1.014 g/mL, 7.6 mmol), and the mixture stirred and monitored by TLC (product Rf=0.43-0.44 in 50% dichloromethane/hexanes). The solution gradually changed color from brown to pale yellow and the reaction proceeded. After 20 hours, the solution was colorless, decaborane (115 mg, 0.941 mmol) was added, at which time the solution became pale yellow again. Another portion of decaborane (103 mg, 0.843 mmol) was added after 4 days, and the reaction stirred an additional six days. After completion, the solvent was evaporated, the residue redissolved, loaded onto a short 2.5 inch columns of silica gel and eluted with 5% ethyl acetate/hexanes. The eluent was collected and concentrated, and the crude product purified by flash chromatography using a slow gradient of 10% dichloromethane/hexanes to 20% dichloromethane/hexanes. Fractions were combined and concentrated to give the desired product ZZZ (1.29 g, 79.6%) as colorless oil.