Acetone → 6-(Aziridin-1-yl)-7-methyl-2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole-5,8-dione

Participants

Reaction Steps

To a solution of 35 mg (0.17 mmol) of 26 in 4 mL of dry methanol, chilled at 0° C., was added 0.5 mL of ethyleneimine. The reaction was stirred at 0° for 30 min and then at room temperature for 1 hour. The solvent was removed in vacuo and the red residue flash chromatographed on silica gel using chloroform as the eluant. The purified product was recrystallized from chloroform/hexane: 20.5 mg (48%) yield; mp 192°-194° C. dec.; TLC (acetone), Rf =0.73; IR(KBr pellet) 1674, 1632, 1575, 1518, 1377, 1338, 1315, 1137, 988 cm-1 ; 1H NMR (CDCl3) δ4.17 (2 H, t, J~7 Hz, C(1) methylene), 2.89 (2H, t, J~7 Hz, C(3) methylene), 2.65 (2 H, quintet, J~7 Hz, C(2) methylene): 2.31 (4 H, s, aziridine protons), 2.02 (3 H, s, 7-methyl): mass spectrum (EI mode) m/z 243 (P+), 228 (P+ -methyl). (Anal. Calcd for C13H13N3O2 : C, 64.18; H, 5.34; N, 17.27. Found: C, 64.02; H, 5.21; N, 16.76.

Provenance & Evidence