| abstract |
The present invention provides a process for the preparation of a compound of formula (2) : the process comprising reacting a compound of formula (1), a base and an alkylating agent R 4 -X in a nitrile-containing polar aprotic solvent to form the compound of formula (2), wherein the process is carried out at a temperature greater than 60 °C; and wherein R 1 , R 2 , R 3 , R 4 , and X are as defined in the specification. |