N-bromobutanimide → HCID 54404171, compound

Participants

Reaction Steps

(±)-(1R*, 2S*, 3S*, 5S*)-3-(Acetoxymethyl)-5-(5,6-dichloro-1H-benzimidazol-1-yl)-1,2-cyclopentanediyl diacetate (1.32 g, 2.98 mmol) in dry N, N-dimethylformamide (6 mL) was heated to 60° C. Portions (ca. 1 mmol each) of N-bromosuccinimide (1.59 g, 8.93 mmol) were added over 5 hours. Heating was continued for an additional 4 hours. Volatiles were removed in vacuo and the residue chromatographed on silica gel. Title compound eluted with 1:1 hexane-ethylacetate as a tan powder (1.1 g, 69%), 1H-NMR identical with recrystallized sample. Such a sample was recrystallized from ethanol-water to a white powder, m.p. 156°-159° C.; 1H-NMR (DMSO-d6)δ: 8.34, 7.97 (both s, 1 each, 2 benzimidazole CH), 5.6 (m, 1, OCH), 5.3 (m, 1, OCH), 5.2-5.0 (m, 1, NCH), 4.4-4.2 (m, 2, OCH2), 2.7-2.5 (m, 1, CH), 2.4-2.0 (m) overlapping 2.1 and 2.07 (both s, total 8, CH2 and 2CH3CO), 1.92 (s, 3, CH3CO); mass spectrum (CI): 527 (6.6), 525 (45), 523 (100), 521 (65, M+1), 257 (48, M-B).

Provenance & Evidence