4-Methoxy-3-buten-2-one is a versatile four-carbon synthon; precursor to the Danishefsky diene; Diels-Alder dienophile; dipolarophile;
electrophilic four-carbon synthon subject to conjugate addition at C-4 followed by elimination of the
methoxide anion; its enolate is a nucleophilic four-carbon building block.
4-Methoxy-3-buten-2-one may be harmful by inhalation, ingestion, or skin absorption; may cause
skin and eye irritation; in addition to standard safety practice, mechanical exhaust is required. Do not breathe
vapor. Store in refrigerator under nitrogen or argon.
