Formaldehyde → 4-hydroxy-N-methylproline

Participants

Reaction Steps

To 40 g (305 mmol) of trans-4-hydroxy-L-proline in 80 ml of water was added 80 ml of 30% aqueous formaldehyde solution and 7.0 g of 5% palladium on carbon catalyst (50% wet), and the mixture was hydrogenated at 50 psig using a Parr Shaker. After 24 hours, the catalyst was recovered by filtration over diatomaceous earth and the filtrate evaporated under reduced pressure to provide 43.5 g (98.3%) of title product; mp 140°-142° C. (decomposition); 1H-NMR (D2O): 4.65 (m, 1H), 4.20 (dd, 1H), 3.97 (dd, 1H), 3.2 (dm, 1H), 2.50 (m, 1H), 2.25 (m, 1H); [alpha]D =-54.8° (c=1.18, H2O).

Provenance & Evidence