Optimization of reaction conditions^a.

Entry	Solvent	Base	Time (h)	Yieldb (%) 2ac
1	DMF	K2CO3	8	58(42)
2	DMF	Na2CO3	8	36(30)
3	DMF	NaHCO3	8	29(8)
4	DMF	KOC(CH3)3	8	52(38)
5	DMF	Cs 2 CO 3	8	89(11)
6	NMP	Cs2CO3	24	70
7	THF	Cs2CO3	24	61
8	DMSO	Cs2CO3	24	79
9	can	Cs2CO3	24	69
10	Dioxane	Cs2CO3	48	—
11	DMF	NaH	8	2
12	DMF	Cs2CO3	8(80 °C)	62(38)
13	DMF	Cs2CO3	8(120 °C)	57(43)

^aUnless mentioned, 4,6-bis(4-methoxyphenyl)-pyrimidin-2(1H)-one (0.16 mmol), base (0.16 mmol), and solvents (5 mL) were used in the reaction; addition of propargyl bromide (0.19 mmol) was done at 0 °C and thereafter stirring at room temperature for 8 h.

^bIsolated yield.

^cYield of 3a is given in parenthesis wherever applicable.