N-bromobutanimide → HCID 67613748, compound

Participants

Reaction Conditions

Reaction Steps

N-Bromosuccinimide (4.54 g, 25.5 mmol) was added to a solution of (±)-(1R*, 2R*, 4S*)-4-(acetoxymethyl)-2-(5,6-dichloro-1H-benzimidazol-1-yl)cyclopentyl acetate (8.95 g, 23.2 mmol) in dry N,N-dimethylformamide (46 mL). The solution was maintained at ca. 70° C. (oil bath) for 5 hours. Volatiles were removed in vacuo and the residual orange syrup chromatographed on silica gel. Title compound was eluted with chloroform as a pale yellow solid (5.14 g, 48%), m.p. 122°-125° C.; 1H-NMR (DMSO-d6)δ: 8.16 (s, 1, benzimidazole H7), 7.95 (s, 1, benzimidazole H4), 5.60-5.55 (m, 1, OCH), 5.12-5.03 (m, 1, NCH), 4.15 (d, J=6.3 Hz, 2, OCH2), 2.66-2.60 (m, 1, CHCH2), 2.29-2.14 (m, 3, CH), 2.06 (s, 3, CH3CO), 1.93 (s overlapped by m, 4, CH3CO+CH); mass spectrum (CI): 469 (5.8), 467 (37.5), 465 (95), 463 (54, M+1), 199 (100, M-B).

Provenance & Evidence