Borane;tetrahydrofuran → HCID 54350117, compound

Participants

Reaction Steps

A borane/THF (48 ml, 48 mmol) solution of the amide from Example 28 (3.50 g, 9.74 mmol) was stirred at reflux for 12 hours under nitrogen. After the solution was quenched with 6N HCl, the THF was removed in vacuo. The acidic residue was warmed on a steambath for 15-20 min and then it was treated with 50% NaOH to afford a pH of 10. The aqueous mixture was extracted with CH2Cl2 and the combined extract was washed with brine and dried (Na2SO4). Solvent removal produced the crude product that was purified by flash silica gel column chromatography using 0.5-4% MeOH in CH2Cl2. There was obtained 1.96 g (58%) of the title compound that was treated with oxalic acid (1.1 eq) in acetone to produce a tan solid: mp 211°- 213° C.; IR (KBr) 3040, 2840, 1720, 1625, 1520, 1345, 1210, 855, 715 and 700 cm-1.

Provenance & Evidence