A Mild, Efficient and General Method for the Synthesis of Trialkylsilyl (Z)-4-Oxo-2-alkenoates and γ-Hydroxybutenolides

2-Trialkylsilyloxyfurans react rapidly with dimethyldioxirane at -78 °C to provide trialkylsilyl (Z)-4-oxo-2-alkenoates whose hydrolysis delivers γ-hydroxybutenolides with high efficiency; a short synthesis of a naturally occurring monoterpene γ-hydroxybutenolide (4) is reported.