Table 1. Conversion of 5-(β-Chlorovinyl)sulfones to 5-(β-Keto)sulfones^a.

entry	substrate	product	yield (%)b
1	5	12	72
2	9a	12	65
3	9b	13	74
4	9c	13	70
5	4	14	59
6	3	15	64

^a(i) 5-(β-Chlorovinyl)sulfones 3–5, 9a–c (0.2 mmol) in NH₃/MeOH, room temperature (rt), 3–12 h; (ii) 0.1 M HCl in MeCN, rt, 2 h.

^bIsolated yields.