Abstract
Transesterification of β-ketoesters with various alcohols has been effected by N,N-diethylaminopropylated silica gel (NDEAP) as a catalyst in refluxing xylene. Generality
of the reaction was demonstrated by successful transesterification of olefinic alcohols,
tertiary alcohols and alcohols having acid- or base-sensitive substituents. The catalyst
has been efficiently recycled more than five times without any re-activation.
Keywords
transesterification - β-ketoester - amine catalyst - silica gel support
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Typical Experimental Procedure: To a stirred solution of menthol (2a, 156 mg, 1 mmol) and methyl acetoacetate (1a, 130 µL, 1.2 mmol) in anhyd xylene (4 mL) was added NDEAP pellets (279 mg, 0.72 mmol/g,
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