ALKYLATION REACTIONS IN NEAR-CRITICAL WATER IN THE ABSENCE OF ACID CATALYSTS

We report successful alkylation reactions in near-critical water in th e absence of added acid catalysts. Water has a strong tendency to ioni ze as the temperature is increased, allowing water in the near-critica l region (250-350 degrees C) to act as an effective acid catalyst. By simultaneously employing near-critical water as the reaction solvent a nd catalyst, the need for environmentally hazardous organic solvents a nd acid catalysts is eliminated. The high hydronium ion content of nea r-critical water proved to be sufficient to synthesize a variety of su bstituted phenols with tertiary, secondary, and even primary alcohols. The reaction products for each of these reactions are reported.