Acetic Anhydride → 5-[4'-(Acetylhydrazinocarbonyl)-2'-methylbiphenyl-4-carbonyl]-1'-ethyl-2,3,6,7-tetrahydrospiro[furo[2,3-f]indole-3,4'-piperidine]

Participants

Reaction Steps

To a stirred solution of 1'-ethyl-5-(4'-hydrazinocarbonyl-2'-methylbiphenyl-4-carbonyl)-2,3,6,7-tetrahydrospiro[furo[2,3-f]indole-3,4'-piperidine] (E61, 1.00 g, 1.96 mmole) in chloroform (30 ml), acetic anhydride (5.76 ml, 0.06 mmole) was slowly added. The solution was stirred at room temperature for approximately 1 hour, then concentrated in vacuo. Toluene was used to azeotrope out the excess acetic anhydride. The residue was dissolved in chloroform, washed with 10% Na2CO3 solution and the organic phase dried (Na2SO4), then concentrated in vacuo. The residue beige solid was chromatographed on silica gel, eluting with 0-12% methanol in chloroform to afford the title compound as a yellow solid (0.87 g, 80%) m.p. 154-157° C.

Provenance & Evidence