7,7-dimethyl-3,4,7,8-tetrahydro-2H-cyclopenta[4,5]pyrrolo[1,2-a]pyrazin-1(6H)-one → 2-Bromo-6-[7,7-dimethyl-1-oxo-3,4,7,8-tetrahydro-1H-cyclopenta[4,5]pyrrolo[1,2-a]pyrazin-2(6H)-yl]benzyl Acetate

Participants

Reaction Conditions

Reaction Steps

A microwave tube equipped with a magnetic stirrer was charged with 167e (301 mg, 1.47 mmol), 2,6-dibromobenzyl acetate 104g (1.1 g, 3.0 mmol), CuI (140 mg, 0.7 mmol) Cs2CO3 (961 mg, 3.0 mmol), N′,N′,N′,N′-tetramethylethylenediamine (0.22 mL, 1.5 mmol) and 1,2-dimethoxyethane (4.1 mL). The mixture was heated in microwave to 150° C. for 3 h. After this time, the mixture was filtered and the resulting solid was washed with 9:1 CH2Cl2/MeOH (50 mL). The combined organics were washed with brine (20 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure. The resulting residue was purified by column chromatography eluting with a gradient of hexanes-ethyl acetate to afford a 32% yield (200 mg) of 167f.

Provenance & Evidence