Silica Chloride Mediated Alkylation of Electron-rich Aromatics by Benzyl or tert-Butyl Chloride

Abstract

o C. TLC monitored the progress of reaction. After completion of the reaction, the mixture was diluted with ethyl acetate and filtered. The solution was washed with sodium carbonate (5% in water) and water. The organic layer separated and evaporated. The residue was applied to a silica gel column. Elution with CCl4 gave pure product. We also tried a similar reaction in the presence of silica gel and HCl (gas) without using silica chloride. The reaction was not successful and the starting materials remained intact. However, we found that this method was applicable for preparation of alkyl aromatic compounds from reaction of tert- butyl chloride and structurally and electronically diverse benzyl chloride with aromatic rings substituted with electron-donating groups (Table 1, entries 2-11 and 13-15). The presence of elec- tron-donating groups in aromatics is necessity for progress of