HIGHLY SELECTIVE FRIEDEL-CRAFTS REACTION OF ELECTROCHMEMICALLY GENERATED 'CATION POOL' USING MICROMIXING

摘要

Highly selective Friedel-Crafts monoalkylation, which was intrinsically difficult to be achieved by conventional methods, has been accomplished by micromixing. N-Acyliminium ion generated by the "cation pool" method was used as an alkylating agent and 1,3,5-trimethoxybenzene was used as an aromatic compound. The reaction in a macro-scale batch reactor (magnetic stirring) gave rise to the formation of a mixture of the monoalkylation product and the dialkylation product in ca. 1:1 ratio, but the use of a multilamination-type micromixer led to selective monoalkylation (92% yield). Based on the micromixing, the selective sequential dialkylation using two different alkylating agents was achieved.