Lithium triethylborohydride → HCID 68231371, compound

Participants

Reaction Conditions

Reaction Steps

SEM dilactam 14 (0.66 g, 0.69 mmol) was dissolved in THF (23 mL) and cooled to −78° C. under an argon atmosphere. Super-Hydride® solution (1.7 mL, 1 M in THF) was added drop wise over 5 minutes while monitoring the temperature. After 20 minutes a small sample was taken and washed with water for LC/MS analysis. Water (50 mL) was added and the cold bath was removed. The organic layer was extracted and washed with brine (60 mL). The combined aqueous layers were washed with CH2Cl2/MeOH (90/10 v/v) (2×50 mL). The combined organic layers were dried with MgSO4, filtered and the solvent removed in vacuo. The crude product was dissolved in MeOH (48 mL), CH2Cl2 (18 mL) and water (6 mL) and sufficient silica gel was added to afford a thick suspension. After 5 days stirring, the suspension was filtered through a sintered funnel and washed with CH2Cl2/MeOH (9:1) (˜200 mL) until product ceased to be eluted. The organic layer was washed with brine (2×70 mL), dried with MgSO4, filtered and the solvent removed in vacuo. Purification by silica gel column chromatography (100% CHCl3 to 96/4 v/v CHCl3/MeOH) afforded the product 15 as a yellow solid (302 mg, 66%). Method 1, LC/MS (2.42 min (ES+) m/z (relative intensity) 660.74 ([M+H]+, 30). 1H NMR (400 MHz, CDCl3) d 7.86 (d, 1H, J=3.6 Hz), 7.78 (d, 1H, J=3.6 Hz), 7.58-7.44 (m, 3H), 7.34-7.20 (m, 3H), 6.88-6.66 (m, 4H), 4.35-4.15 (m, 6H), 3.95-3.75 (m, 7H), 3.39-3.22 (m, 1H), 3.14-3.04 (m, 1H), 2.93-2.85 (m, 1H), 2.46-2.36 (m, 2H), 1.49-1.41 (m, 1H), 0.80-0.72 (m, 2H), 0.58-0.51 (app. s, 2H) ppm.

Provenance & Evidence