Phosgene → 5-Isocyanato-1,3-dioxaindane

Participants

Reaction Steps

A mixture of 3,4-methylenedioxyaniline (275 mg; 2.0 mmol) in toluene (15 ml) and phosgene (4.75 ml; 20% in toluene; 9 mmol) was refluxed for 6 h. The solvent was removed under reduced pressure to give crude 3,4-methylenedioxyphenylisocyanate. The crude product was added to 3-[4-(2-chlorophenyl) -1-piperazinyl]propanol (510 mg; 2.0 mmol) in toluene (30 ml) was refluxed for 16 h. The reaction mixture was then concentrated and submitted to flash chromatography on silica gel 60 eluting with toluene graduated to toluene/ethyl acetate (1:3). The product was taken up in ethanol which was treated with hydrogen chloride in ether. Recrystallization from methanol/ether afforded 550 mg of the title compound. M.p. 211°-213° C. MS (70 eV): m/z 37%, M+), 254 (28), 209 (100), 163 (75), 138 (32), 70 (42).

Provenance & Evidence