Sulfuric acid magnesium salt (1:1) → N-{3-{[tert-butyl(dimethyl)silyl]oxy}-5-[(1E)-3-methoxyprop-1-en-1-yl]benzyl}cyclopropanamine

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Reaction Steps

To a solution of 3-{[tert-butyl(dimethyl)silyl]oxy}-5-[(1E)-3-methoxyprop-1-en-1-yl]benzaldehyde from the previous step (1 eq.) in dichloromethane (0.5 M) was added cyclopropylamine (2 eq.) and magnesium sulfate (1.5 eq.). The resulting suspension was stirred at RT for 12 h. The insolubles were removed via filtration. Concentration of the filtrate in vacuo afforded the crude imine as a yellow oil. This was then taken up in methanol (0.3 M) and then added at 0° C. sodium borohydride (1.5 eq.) portionwise over 5 min. The reaction mixture was slowly warmed to RT over 1 h and then stirred at RT for 2 h. After carefully quenching with sat. aq. NaHCO3, the resulting mixture was extracted with ether. The combined organic extracts were washed with water and brine, dried over MgSO4 and filtered. Concentration of the filtrate in vacuo afforded the title compound as a golden, yellow oil.

Provenance & Evidence