Przemysl Chemiczny, Vol.91, No.10, 1931-1934, 2012
Optimization of conditions of condensation of phenol with methyl pyruvate in acidic 1-n-butyl-3-methylimidazolium aluminium chloride ionic liquid medium
PhOH was condensed with MeOCOCOMe to MeOCO(Me) C(p-C6H5OH)(2) (yield 31.9-53.1%) in N-butyl-N-methylimidazolium AlCl4 ionic liq. (optionally after addn. of CHCl3) at 20-60 degrees C for 1-20 h. Neither CHCl3 addn. nor increasing the product yield reaction temp. or time resulted in substantial increasing the product yield and reaction selectivity. The main reaction by-products were m-OHC6H4C(Me)(OH) COOMe and 3-methyl-3-hydroxycumaranon-2.