2,3-Diaminobenzoic acid methyl ester → Methyl 2-butyl-1H-benzimidazole-4-carboxylate

Participants

Reaction Steps

Using the procedure of Step A of Example 1, 2.5 g of methyl 2,3-diaminobenzoate [J. Chem. Soc., Vol. 117 (1920) p 775 and CAN. J. Chem., Vol.55 (1977), p. 1653 to 1657] and 2.73 g of ethyl pentanimidoate hydrochloride [J.A.C.S., Vol. 64, p. 1827 (1942)] were reacted to obtain 3.05 g of the desired product which after crystallization from essence G melted at approximately 85° C. The analytical sample was obtained by two successive crystallizations of 280 mg of product from isopropyl ether to obtain 100 mg of the product melting at 97° C.

Provenance & Evidence