Table 1.

Yields of 3 under ultrasound solvent-free conditions

Entry	Power/W	Time/min	Yielda/%
1	200	150	38
2	250	120	41
3	300	80	46
4	350	50	54
5	400	50	54

Aniline (10 mmol), α-bromoacetophenone (20 mmol), sodium carbonate (10 mmol), and 2 mol% PEG 400

^aIsolated yield