M. R. Grimmett 
Imidazole and Benzimidazole Synthesis [PDF ebook] 

Imidazole and Benzimidazole Synthesis is a comprehensive survey of the known methods of syntheses and ring modification. It brings together the multitude of synthesis of the imidazole ring in a systemic way interms of specific bond formation, and recommends the most attractive synthetic approaches. It also collects non-ring-synthetic approaches to classes of compounds such as nitro-, halogeno-, and amino-imidazoles, and covers the synthesis of N-substituted compounds and preparations of specific isomers. The only book in print dealing specifically with this topic Comprehensive survey of the known methods of synthesis and ring modification Recommends the most attractive synthetic approaches