Boric Acid Catalyzed Convenient Synthesis of Benzimidazoles in Aqueous Media

Table 2

Synthesis of benzimidazole 3a–o by using boric acid in water.

Entry	Diamine	Aldehydes	Products	Time (min)	Yield (%)^a
1				30	95
2				40	90
3				45	89
4				60	89
5				60	89
6				60	88
7				60	88
8				60	86
9				60	85
10				10	98
11				10	95
12				15	90
13				5	95
14				5	95
15				20	90

^aIsolated yield.