Table 1. Reaction of Enolates of Active Methylene Compounds (a–e, 50-fold Excess) with Dehydrobenzene Diradicals of Enediynes (1–3) Generated at Optimized Temperatures in DMSO: Isolated Products (Yields in Parentheses).

temperature, time →	55 °C, 12 h	85 °C, 72 h	75 °C, 24 h
enolate ↓, enediyne →	1	2	3
a	4a(29)	5a(55)	6a(46)
b	4b(25)	5b(57)	6b(44)
c	4c(19)	5c(51)	6c(37)
d	4d(24)	5d(54)	6d(43)
e	4e(trace)	5e(35)	6e(22)