Pyridine → 3-(N Ethyloxycarbonyl 1,4 dihydro-4 pyridyl)-2-(4-methoxyphenyl)6,7-dihydro [5H]-pyrrolo[1,2-a]imidazole

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Reaction Conditions

Reaction Steps

A stirred solution of 2.8 g (13.1 mmoles) of 2-(4-methoxyphenyl)-6,7-dihydro [5H]-pyrrolo[1,2-a]imidazole, prepared as described above, and 6.2 q (78.4 mmoles) of dry pyridine in 30 ml of dry CH2Cl2 was treated dropwise over 1 hour at 5 ° C. under argon atmosphere with 4.25 g (30.2 mmoles) of ethyl chloroformate. After stirring for 1 hour an additional 3.1 g (39.2 mmoles) of pyridine was added, followed by 2.15 g (19.8 mmoles) of ethyl chloroformate added over 2 hours. The mixture was stirred overnight at 25 ° C., then poured into ice water made alkaline with Na2CO3 and extracted with CH2Cl2. The organic phase was sequentially washed with 0.2 N HCl, water, and aqueous K2CO3 solution, dried over Na2SO4 and stripped in vacuo to afford the titled compound as an amber resin.

Provenance & Evidence