Aluminium lithium hydride → HCID 86587688, compound

Participants

Reaction Conditions

Reaction Steps

Powdered lithium aluminum hydride (3.05 g, 80.4 mmol) was carefully added portionwise to a stirred solution of 2-benzo[b]thiophen-3-yl-cyclopropanecarboxylic acid methoxy-methyl-amide (3.50 g, 13.4 mmol) in anhydrous tetrahydrofuran (300 ml) at −40° C. under N2. The resulting mixture was stirred at −40° C. for 3 h. The reaction was quenched with ethyl acetate (100 ml) and allowed to warmed to room temperature. After 20 min, water (5 ml) was added followed by a solution of aqueous sodium hydroxide (5N, 5 ml). After stirring for 30 min at room temperature the aluminum salts were removed by vacuum filtration. The salts were washed with ethyl acetate (100 ml) and the combined filtrates were concentrated in vacuo. The crude material was purified by silica gel column chromatography (10% ethyl acetate in hexane) to give trans-2-benzo[b]thiophen-3-yl-cyclopropanecarbaldehyde (2.02 g, 75%). 1H NMR (500 MHz, CDCl3) 9.48 (1H, d, J=4.57 Hz), 7.84 (2H, dd, J=17.09, 7.33 Hz), 7.41 (2H, m), 2.80 (1H, m), 2.17 (1H, m), 1.78 (1H, m), 1.59 (1H, m); MS m/e 203.22 (M+H)+.

Provenance & Evidence