N-METHYL-N-(4-NITROBENZYL)AMINE HYDROCHLORIDE

Preparation 33A; N-methyl(4-nitrophenv0methanamiπe; OGeneral procedure: The desired nitro-substituted benzaldehyde (1 eq, 13.2 mmol, 2.0 g), methylamine (40percent watersolution, 1.1 eq, 14.5 mmol, 0.95 mL) and molecular sieves (3A, 100 mg) were introduced in a screw cap vialand the mixture was heated at 80°C for 24h. After cooling to RT, the mixture was diluted with chloroform (3mL) and filtered. The solvent was removed by rotary evaporation and the crude obtained was redissolved inmethanol (30 mL) and cooled to 0 °C. NaBH4 (1.1 eq, 14.5 mmol, 550 mg) was added in three portions andthe resultant mixture allowed warming to RT and reacting for 24 h. The mixture was then quenched with aq.NH4OH 5percent (10 mL) and the solvent was concentrated by rotary evaporation. The obtained aqueous layer wasextracted with CH2Cl2 (3 x 10 mL). The combined organic extracts were dried over Na2SO4, filtered and thefiltrate was concentrated by rotary evaporation. The residue was purified by silica gel flash chromatographyor distillation under vacuum to give the title compound.