Lithium borohydride → 1,1-Dimethylethyl 6-cyano-1-(2-hydroxyethyl)-5-methyl-3,4-dihydro-2(1H)-isoquinolinecarboxylate

Participants

Reaction Steps

To a solution of 1,1-dimethylethyl 1-[2-(butyloxy)-2-oxoethyl]-6-cyano-5-methyl-3,4-dihydro-2(1H)-isoquinolinecarboxylate (Preparation 18; 2.15 g, 5.56 mmol) in ethanol (10 ml) and diethyl ether (40 ml) was added lithium borohydride (2M solution in tetrahydrofuran, 4.17 ml; 8.34 mmol) at 25° C. under nitrogen. After 1.5 h at 25° C., the solvent was removed, and the residue dissolved in ethyl acetate. The solution was washed with 1N hydrochloric acid, and the aqueous layer further extracted with ethyl acetate. The combined organic phases were washed with saturated sodium bicarbonate, dried over MgSO4 and concentrated in vacuo to give the title compound (1.70 g) as a white foam.

Provenance & Evidence