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Electrochemical N-arylation of azoles in MeOH using undivided electrolysis of their mixtures with 1,4-dimethoxybenzene

“…This explains, for instance, the appearance of compounds 6 in the electrolysis products of a DMP-DMB mixture containing no special additives. 2 The above presented results indicate an important role of the acid catalysis, due to which (see Scheme 5) trans formations 8 → 9 and 8 → 10 become reversible, to a noticeable extent, for all azoles under study. These factors enhance the role of the third reaction route involving arenonium cation 8 and producing ortho substitution product 6.…”

“…That is why only CL additives produce N arylation products in the electrolysis involving low basicity azoles, while the efficiency of these additives is less pronounced for elec trolysis involving high basicity azoles. 2 Electrophile Е + (being radical cation 1, see Scheme 1) predominantly undergoes the ipso attack by the nucleo phile 1,2 to form a radical, which is further oxidized to cation 4. However, a solvent molecule can act as a nu cleophile in the electrolysis of an azole-DMB mixture in MeOH.…”

“…As a result, product 6 was obtained in high yield. 2 In future, we are intending to develop this approach to the synthesis of N arylazoles. (1 : 1, vol/vol) mixture were recorded on a Bruker AC 300 instrument.…”

“…According to the pro cess mechanism, the non ionized azole species mainly acts as a nucleophile interacting with radical cation 1. 1,2 This species exists in solution as complexes Az...H•B, where B is a base, which can be collidine or high basicity azole molecules added to the electrolyzed solution.…”

Indirect Electrochemical N-Dimethoxyphenylation of 3-Nitro-1,2,4-triazole and Tetrazole

“…According to [1][2][3][4], diaphragmless electrolysis of a mixture azole/1,4-dimethoxybenzene (DMB) in an environment of MeCN leads (scheme 1) to the formation of 1,4-dimethoxy-2-(azolyl-1)benzenes ( 4 ) and hydrolytically labile 1,4-dimethoxy-1,4-di-(azolyl-1)cyclohexa-2,5-dienes ( 7 ). In agreement with [3], the ratio between these products is defined by the regrouping of an intermediate cation of 1,4-dimethoxy-1-(azolyl-1)arenonium 1 into a cation of 1-(azolyl-1)-2,5-dimethoxyarenonium 3 , occurring via a mechanism of kine -substitution, and in so doing it was assumed that conversion 1 into 7 bears in a noticeable degree a reversible character.…”