反应详情

Scheme 9 provides a synthetic route to the 1-carboxymethyl-5-N-ethyl phenazine derivative (42). The bromo derivative (37) is formed by reacting 1-methyl phenazine (36) (available from Apin Chemicals, UK) with N-bromosuccinimide in the presence of benzoyl peroxide and a solvent. Carbon tetrachloride is a particularly suitable solvent for the bromination reaction. Reaction of the bromide (37) with KCN in a suitable solvent, such as, for example, DMF, gives the 1-cyanomethyl phenazine derivative (38). Acid hydrolysis of the cyanophenazine (38) provides the 1-carboxymethyl phenazine (39). The acid group of compound (39) is converted to a methyl ester by reaction with methanol and HCl to give the phenazine ester (40). Ester (40) can be N-alkylated with dimethyl sulfate in the presence of potassium carbonate to give the 5-ethyl phenazine ester (41). Hydrolysis of the ester (41) with dilute hydrochloric acid provides the 5-ethyl-1-carboxymethyl phenazine (42).

1. customfor the bromination reaction