3-Methoxy-1-(4-methoxybenzyl)-4-propionyl-5,6-dihydro-1H-pyridin-2-one → 1-Cyclopentyl-3-ethyl-6-(4-methoxybenzyl)-5,6-dihydro-1H-pyrazolo[3,4-c]pyridin-7(4H)-one

Participants

Reaction Conditions

Reaction Steps

3-Methoxy-1-(4-methoxybenzyl)-4-propionyl-5,6-dihydro-1H-pyridin-2-one (14.471 kg, 47.76 moles) was dissolved in tetrahydrofuran (10.5 gal, 39.7 L) in a clean and dry 100 gallon tank. Cyclopentylhydrazine dihydrochloride (7.664 kg, 44.3 moles) was added and the reaction mixture warmed slowly to 88° C. while nitrogen was swept over the reaction to remove methanol, THF, and HCl. The reaction was monitored by HPLC until the conversion was complete which required heating overnight in most cases. The pot reaction product was a thick dark oil. A sample of 1-cyclopentyl-3-ethyl-6-(4-methoxybenzyl)-1,4,5,6-tetrahydropyrazolo[3,4-c]pyridin-7-one was isolated for characterization.

Provenance & Evidence