Sodium Cyanate → 5-ureidospiro[benzo[b]furan-2(3H),1'-cyclopropane]-3-one

Reaction equation

[NH2:1][C:2]1[CH:13]=[CH:12][C:5]2[O:6][C:7]3([C:10](=[O:11])[C:4]=2[CH:3]=1)[CH2:9][CH2:8]3.[O-:14][C:15]#[N:16].[Na+]>CO.C(O)(=O)C>[NH:1]([C:2]1[CH:13]=[CH:12][C:5]2[O:6][C:7]3([C:10](=[O:11])[C:4]=2[CH:3]=1)[CH2:9][CH2:8]3)[C:15]([NH2:16])=[O:14]

Participants

Procedure

To a solution of 5-aminospiro[benzo[b]furan-2(3H),1'-cyclopropane]-3-one (1.75 g.) in methanol (10 ml.) and acetic acid (5 ml.) was added dropwise 2 ml. of aqueous solution of sodium cyanate (130 mg.), and the mixture was stirred for 2 hours at room temperature. To the reaction mixture was added ice-water, and the precipitated crystals were collected by filtration and recrystallized from ethanol to give colorless needles of 5-ureidospiro[benzo[b]furan-2(3H),1'-cyclopropane]-3-one (0.74 g.).