Sulfuric acid magnesium salt (1:1) → N-[3-[(1E)-3-Methoxyprop-1-en-1-yl]-5-(trifluoromethyl)benzyl]cyclopropanamine

Participants

Reaction Steps

3-[(1E)-3-Methoxyprop-1-en-1-yl]-5-(trifluoromethyl)benzaldehyde (1 eq.) from the previous step and cyclopropylamine (2 eq.) were combined in CH2Cl2 (0.2 M). To this was then added MgSO4 (1.5 eq.) and the resulting suspension was stirred at RT for 18 h. The insolubles were then removed via filtration through a pad of celite and the filtrate was concentrated in vacuo. The crude imine thus obtained was then re-taken up in a 2:1 (v/v) mixture of THF:MeOH (0.2 M). To this solution was added sodium borohydride (5 eq.) portionwise and the resulting mixture was stirred at RT for 18 h. The reaction was quenched with saturated aqueous sodium bicarbonate and extracted with ethyl acetate. The combined organic extracts were then washed with brine, dried over Na2SO4, filtered and the filtrate concentrated in vacuo. Purification of the crude product by way of flash chromatography (SiO2, 9:1 (v/v) Hex:EtOAc→EtOAc) afforded the title compound.

Provenance & Evidence