Patent ID: 8236946

Claim:
A process for the preparation of a compound of the formula (III) by the triflation of a ketone of the formula (II) wherein R′ represents hydrogen or a lower acyl group having 2 to 4 carbon atoms; or a protected derivative thereof; the triflating step being conducted in the presence of a base comprising a tertiary or heterocyclic amine such that the pK a of the conjugate acid at 25° C. is within the range 5.21 to 12, wherein the base is selected from the group consisting of pyridine, 2,6-lutidine, N-methylmorpholine, 1,4-diazabicyclo[2.2.2]octane (DABCO), trimethylamine, triethylamine, N,N-diisopropylethylamine (DIPEA), quinuclidine and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).