proline dl-form → (1aR,5aR)-2-(5-Methoxy-pyridin-2-yl)-1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalene-4-carboxylic Acid Ethyl Ester

Participants

Reaction Conditions

Reaction Steps

A 20 mL scintillation vial was charged with (1aR,5aR)-1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalene-4-carboxylic acid ethyl ester (492 mg, 2.56 mmol), 2-iodo-5-methoxypyridine (662 mg, 2.82 mmol), DL-proline (58.9 mg, 0.512 mmol), copper(I) iodide (48.7 mg, 0.256 mmol), and potassium carbonate (708 mg, 5.12 mmol). The vial was flushed with nitrogen, and added DMSO (15 mL). The reaction was stirred under nitrogen at 75° C. for 15 h. The reaction was filtered then purified by HPLC to provide the title compound (279 mg) as a white solid. LCMS m/z=300.3 [M+H]+; 1H NMR (400 MHz, CDCl3) δ ppm 0.45 (td, J=4.7, 3.3 Hz, 1H), 1.23 (td, J=8.0, 4.8 Hz, 1H), 1.39 (t, J=7.2 Hz, 3H), 2.21-2.27 (m, 1H), 2.77-2.82 (m, 1H), 2.85 (d, J=16.6 Hz, 1H), 2.97 (dd, J=16.6, 6.4 Hz, 1H), 3.90 (s, 3H), 4.38 (q, J=7.2 Hz, 2H), 7.34 (dd, J=8.8, 2.9 Hz, 1H), 7.98 (dd, J=9.0, 0.6 Hz, 1H), 8.13 (dd, J=3.0, 0.5 Hz, 1H).

Provenance & Evidence