Methylamine → N-(3-Chloro-4-nitrobenzylidene)methanamine

3-Chloro-4-nitrobenzaldehyde (251 mg 1.35 mmole) was dissolved in dichloromethane (2 mL) and methylamine, 2M in THF (0.88 mL, 1.76 mmole) was added along with 3A Sieves (400 mg). The reaction was stirred at room temperature for 18.5 hours. The sieves were filtered and washed with more dichloromethane. The filtrate was evaporated, however only partial conversion to the imine was observed. The residue was redissolved in dichloromethane (2 mL) and methylamine. 2M in THF (1.0 mL, 2.0 mmole) was added along with powdered 3A Sieves (400 mg). The reaction was stirred at room temperature for a further 16.5 hours. The sieves were filtered and washed and the filtrate evaporated to give the title compound as an oil which quickly crystallised (199 mg). 1H-NMR (CDCl3, 500 MHz): δ 3.60 (d, J=1.89 Hz, 3H), 7.73 (dd, J=1.89, 8.51 Hz, 1H), 7.93 (m, 2H), 8.30 (q, J=1.58 Hz, 1H).