Triethylamine → Benzenepropanoic acid, 4-(cyanomethyl)-, 1,1-dimethylethyl ester

Participants

Reaction Steps

A mixture of 5 g of p-bromophenylacetonitrile, 4.6 ml of t-butyl acrylate, 57 mg of palladium diacetate, 310 mg of tri-o-tolylphosphine and 12 ml of triethylamine is refluxed for 5 hours. The reaction mixture is diluted with ethyl acetate and washed with 10% HCl and saturated sodium bicarbonate solution. After drying over magnesium sulfate the solvent is removed in vacuo. This material is dissolved in ethanol and hydrogenated over 1.1 g of 10% palladium on carbon catalyst for 3 days at 3 atmospheres pressure of hydrogen. After filtration the solvent is removed in vacuo and the residue is chromatographed on silica gel with ether/hexane (1:1) as the eluent to afford p-(2-t-butoxycarbonyl-ethyl)-phenylacetonitrile; 2.8 g of this product is dissolved in 90 ml of tetrahydrofuran and 50 ml of methanol and to this is added 6.2 g of cobalt chloride in 90 ml of water followed by 2.1 g of sodium borohydride in small portions. After filtration and removal of solvent, the residue is chromatographed on silica gel with 7.5% methanol saturated with ammonia in methylene chloride as the eluent to afford p-(2-t-butoxycarbonyl-ethyl)-2-phenethylamine as an oil.

Provenance & Evidence