Furfurylamine → (2-Furylmethyl)[(4-propoxyphenyl)methyl]amine

4-Propoxy benzaldehyde (5 g, 31 mmol) and furfuryl amine (3.9 g, 40 mmol) in a mixture of methanol (50 mL), trimethylorthoformate (10 mL) and AcOH (˜1 mL) were stirred at room temperature, under an atmosphere of nitrogen for 16 hours. Sodium borohydride (1.4 g, 35 mmol) was added in 4 portions, over a period of 30 minutes (exothermic reaction). The reaction was stirred for an additional 2 hours at room temperature. The solvent was removed on the rotovap and the residue taken up in ethyl acetate (150 mL). The organic phase was washed with H2O (200 mL) and aqueous phase was back extracted with ethyl acetate (2×, 100 mL). The combined organic layers were concentrated and the residue was purified on silica gel (70% ethyl acetate in hexanes with ˜2% triethylamine) to afford N-(4-propoxybenzyl)-1-(furan-2-yl)methanamine (5.3 g, 75%) as a yellow oil. NMR (CDCl3, 400 MHz): δ 1.03 (t, J=7.2 Hz, 3H), 1.79 (m, J=6.4 Hz, 2H), 3.71 (s, 2H), 3.76 (s, 2H), 3.90 (t, J=6.8 Hz, 2H), 6.17 (d, J=3.2 Hz, 1H), 6.32 (m, 1H), 6.85 (d, J=8.4 Hz, 2H), 7.22 (d, J=8.8 Hz, 2H), 7.37 (m, 1H).

1. custom(exothermic reaction)
2. stirringThe reaction was stirred for an additional 2 hours at room temperature
3. customThe solvent was removed on the rotovap
4. washThe organic phase was washed with H2O (200 mL) and aqueous phase
5. extractionwas back extracted with ethyl acetate (2×, 100 mL)
6. concentrationThe combined organic layers were concentrated
7. customthe residue was purified on silica gel (70% ethyl acetate in hexanes with ˜2% triethylamine)

ORD record

ord-985f1e3df5be4254a6fbecd80abbd365

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08445692B2