| SYNTHESIS |
Acids, bases avoid mutual destruction. Authors have managed to carry out sequences of acid- and base-catalyzed reactions in one pot by sequestering the acids and bases from one another. Authors keep the acid and base from neutralizing one another by entrapping them in silica gel matrices. Acids are molybdic acid or a sulfonated perfluoro resin. Bases are N-2-aminoethylaminopropylated silica or 1,5,7-triazabicyclo[4.4.0]dec-5-ene. The chemists demonstrate their technique by heating benzene solutions of pinacol, malononitrile, and entrapped sulfonated resin and aminopropylated silica. In the sequence shown, the acid catalyzes rearrangement of pinacol to pinacolone, which undergoes base-catalyzed condensation with malononitrile to yield 83% overall of a 1,1-dicyano-1-butene
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