Sodium borohydride → HCID 69640587, compound

Reaction equation

[CH2:1]([O:8][C:9]1[CH:26]=[CH:25][C:24]2[C@@H:23]3[C@H:14]([C@H:15]4[C@@:19]([CH2:21][CH2:22]3)([CH3:20])[C:18](=[O:27])[CH2:17][C@H:16]4[C:28]#[N:29])[CH2:13][CH2:12][C:11]=2[CH:10]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[BH4-].[Na+]>C1COCC1.CO>[CH2:1]([O:8][C:9]1[CH:26]=[CH:25][C:24]2[C@@H:23]3[C@H:14]([C@H:15]4[C@@:19]([CH2:21][CH2:22]3)([CH3:20])[C@@H:18]([OH:27])[CH2:17][C@H:16]4[C:28]#[N:29])[CH2:13][CH2:12][C:11]=2[CH:10]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

Procedure

A solution of 558 mg (1.45 mmol) of 45 in THF (6.6 mL) and MeOH (34 mL) was stirred at rt as 400 mg (10.6 mmol) of NaBH4 was added in small portions over 10 min. The reaction was stirred at rt under N2 for 3.5 h, the solvent was evaporated and the residue was dissolved in EtOAc (100 mL) and H2O (50 mL). The phases were separated and the aqueous phase was extracted with EtOAc (2×, 70 mL). Combined organic extracts were dried over Na2SO4 and concentrated in vacuo giving a yellow foam which was used without purification in the next step. Data for 46: TLC, T-2, Rf 0.22; 1H NMR (400 MHz, CDCl3) δ 1.07 (s, 3H, H-18), 3.75 (t, 1H, J=8.7 Hz, H-17α), 5.05 (s, 2H, benzylic-H), 6.75 (d, 1H, J=2.7 Hz, H-4), 6.80 (dd, 1H, J=8.5, 2.7 Hz, H-4), 7.21 (d, 1H, J=8.5 Hz, H-1), 7.33–7.45 (m, 5H, Ar—H).