Hydrochloric Acid → HCID 66811622, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 2-({2-[(4-butyl-2,3-dioxopiperazin-1-yl)(phenyl)acetyl]hydrazino}carbonyl)-3-phenylpiperidine-1-carboxylate (15.5 mg, 0.026 mmol) in 1,2-dichloroethane (1.5 ml) was added Burgess reagent (21.9 mg, 0.078 mmol). The reaction vessel was sealed and heated to 120° C. for 10 min in an Emry's Optimizer microwave reactor. Additional Burgess reagent (21.9 mg, 0.078 mmol) was added to the solution, and the reaction was sealed and heated again to 120° C. for 10 min in a microwave reactor. The reaction was concentrated in vacuo to yield the cyclodehydration product. A solution of the crude material in EtOAc (5 ml) at 0° C. was saturated with HCl gas and allowed to stir for 2 h. The reaction was concentrated in vacuo and purified via reverse phase HPLC to yield 1-butyl-4-(phenyl[5-(cis-3-phenylpiperidin-2-yl)-1,3,4-oxadiazol-2-yl]methyl)piperazine-2,3-dione. HRMS (ES, M+H), cal'd for C28H33N5O3: 488.2656, found: 488.2646. 1H NMR (400 MHz, CD3OD) δ 7.42-7.22 (m, 7H), 7.09 (m, 3H), 6.87 (m, 2H), 5.36 (dd, J=14.6, 5.4 Hz, 1H), 3.88 (t, J=13.2 Hz, 1H), 3.53 (m, 1H), 3.44 (m, 6H), 3.24 (m, 1H), 3.11 (m, 1H), 2.55-2.38 (m, 1H), 2.25 (m, 1H), 2.00 (m, 2H), 1.56 (m, 2H), 1.33 (sext, J=7.4 Hz, 2H), 0.94 (t, J=7.2 Hz, 3H).

Provenance & Evidence