(Diethylamino)sulfur trifluoride → BW-4030W92, (-)-

Participants

Reaction Conditions

Reaction Steps

The fluorination is effected under conditions at which racemisation of the 6-hydroxymethyl and 6-fluoromethyl (-)enantiomers does not occur. The temperature should thus be less than 80° C., for example less than 50° C. Fluorination can be effected, for example, by the redaction of (-)-2,4-diamino-5-(2,3-dichlorophenyl)-6-hydroxymethyl pyrimidine with diethylaminosulphur trifluoride (DAST). That may be achieved in dichloromethane at -78° C. The solution is then stirred whilst allowing to warm to -10° C. over four and a half hours to give (-)2,4-diamino-5-(2,3-dichlorophenyl)-6-fluoromethyl pyrimidine.

Provenance & Evidence