General method 2-substituted benzimidazoles

1-Hydroxymethylbenzimidazole (see Section 7.1.2), made from benzimidazole (1.57 g, 13.3 mmol) and either paraformaldehyde or aqueous formaldehyde is suspended in dry THF (60 ml) in a flask which has been evacuated and flushed (three times) with dry argon. The mixture is allowed to warm 

Novikov, I V. Khmel nitskii, O. V. Lebedev, V. V. Sevost yanova and L. V. Epi-shina, Chem. Heterocycl. Compd. USSR (EngL Transl.) 6, 669 (1970). 

Moreno-Manas, J. Bassa, N. Llado and R. Pleixats, J. Heterocycl. Chem. 27, 673 (1990). 

Stensio, K. Wahiberg and R. Wahren, Acta Chem. Scand. 27. 2179 (1973). 

Wakefield, Organolithium Methods. Academic Press, London, 1988. 

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