Diisobutylaluminum hydride → Boc-(S)-3-Amino-3-phenylpropanal

Participants

Reaction Conditions

Reaction Steps

To a dry, cooled (−78° C.) solution of ethyl (3S)-3-[(tert-butoxycarbonyl)amino]-3-phenylpropanoate from Step A (1.00 g, 3.41 mmol) was added a solution of DiBAl-H (6.82 mL, 6.82 mmol, 1 M in CH2Cl2) slowly over 30 min. After an additional 30 min of stirring at −78° C., the reaction was quenched by the rapid addition of saturated aqueous Rochelle's salt (32 mL). The cooling bath was then removed and the reaction was allowed to rapidly stir until a noticeable decrease in the amount of emulsion was observed. The layers were separated and the aqueous layer was extracted with CH2Cl2 (2×30 mL). Combined organics were dried over sodium sulfate, filtered and concentrated in vacuo to give an oil. This oil was purified by silica gel chromatography, eluting with a gradient of EtOAc:hexanes 5:95 to 40:60, to give the title compound. MS: m/z=150 (M−CO2C4H7).

Provenance & Evidence