Trifluoroacetic acid → HCID 58093190, compound

Participants

Reaction Steps

In scheme (V), 5-(tert-butoxycarbonyl)-4-(tert-butoxycarbonylamino)-2,6-dichloronicotinic acid (4) is first treated with 25% trifluoracetic acid (TFA) in dichloromethane (DCM) at room temperature (25° C.) for 2 hours, removing one of the two Boc groups and forming 4-amino-5-(tert-butoxycarbonyl)-2,6-dichloronicotinic acid (5). A stronger condition (reflux at 60° C., 25% TFA in DCM, 2 h) is then used to maximize hydrolysis of the tert-butyl ester of 4-amino-5-(tert-butoxycarbonyl)-2,6-dichloronicotinic acid (5) and obtain 4-amino-2,6-dichloropyridine-3,5-dicarboxylic acid (6).

Provenance & Evidence