Table 5.

Seven-membered enaminone preparation

entry	ynonea		enaminone		methodb	yieldc
1		2u		3u	A	60
					B	64
2		2v		3v	A	64
					B	63
3		2w		3w	A	81
					B	84
4		2x		3x	A	66
					B	65

^aSee Supporting Information for the synthesis of ynones 2u–2x.

^bMethod A: i) 4N HCl/dioxane, 15 min. ii) K₂CO₃, MeOH; Method B: i) Nal (3 equiv), formic acid, 6–24 h. ii) K₂CO₃, MeOH;

^cIsolated yield.