Ammonia → 6'-Bromo-5''-methyl-3'H-dispiro[cyclobutane-1,2'-indene-1',2''-imidazol]-4''-amine

Participants

Reaction Conditions

Reaction Steps

6′-Bromo-5″-methyl-3′H-dispiro[cyclobutane-1,2′-indene-1′,2″-imidazole]-4″(3″H)-thione (Example 54 Step 3, 1.62 g, 4.83 mmol) and ammonia (7M in MeOH, 15.2 mL, 106 mmol) were mixed together in a microwave vial. The vial was sealed and the reaction was heated at 90° C. for 30 min in a microwave reactor. The mixture was concentrated and the residue was dissolved in ammonia (7M in MeOH, 15.2 mL, 106 mmol), and heated once more at 90° C. for 30 min in a microwave reactor. This cycle was repeated four more times. After evaporation of the solvent, the crude was acidified with 2 M aq. hydrochloric acid, and washed with EtOAc. The aqueous phase was treated with 2M NaOH until basic pH was reached and then it was extracted with EtOAc. The organic phase was dried over MgSO4 and concentrated. The organic phase was then acidified with 2M citric acid. The aqueous phase was treated with 2M NaOH until basic pH was reached and then it was extracted with EtOAc. The organic phases containing the title compound were combined, dried over MgSO4 and concentrated. The residue was dissolved in EtOAc and was washed with 50% aq. NaOH The organic layer was dried over MgSO4 and concentrated to afford the title compound (1.0 g, 65% yield): NMR: 1H NMR (500 MHz, DMSO-d6) δ ppm 1.48-1.67 (m, 4 H), 1.73-1.86 (m, 1 H), 2.08-2.17 (m, 1 H), 2.19 (s, 3 H), 3.06-3.20 (m, 2 H), 6.65 (br. s., 2 H), 6.71 (d, 1 H), 7.26 (d, 1 H), 7.35 (dd, 1 H); MS (ES+) m/z 318 [M+H]+.

Provenance & Evidence