Table 3.

Conversion of adducts 4 to oxazoles 5.

entry	R1	R2	base	product	yield, %
1a	p-MeC6H4	Ph	BuLi	5a	13
2a,b	p-MeC6H4	Ph	BuLi	5a	24
3	p-MeC6H4	Ph	BuLi	5a	82
4	p-MeC6H4	Ph	t-BuOK	5a	27
5	p-MeC6H4	Ph	t-BuOLi	5a	66
6	p-MeC6H4	Bu	BuLi	5b	45
7	p-MeC6H4	t-Bu	BuLi	5c	56
8	p-MeC6H4	Me3Si	BuLi	5d	52
9	Et	Ph	BuLi	5e	70

^aDry THF was used as solvent; ^b2 equiv of H₂O were added.