Table 1. Screening of the Lewis Acid Catalysts for Ugi-Tetrazole Adduct.

entry	catalyst	conc. (equiv)	yield (%)a
1	-	-	45
2	ZnCl2	0.1	72
3	SnCl2	0.1	60
4	(CF3SO3)2Zn	0.1	62
5	CF3SO3Ag	0.1	43
6	CF3SO3K	0.1	47
7	(CF3SO3)2Mg	0.1	75
8	CF3SO3Li	0.1	53
9	(CF3SO3)3In	0.1	38
10	(CF3SO3)3Al	0.1	47

^aIsolated yield.