Chemists have long valued ethyl acetoacetate as one of organic synthesis’s most adaptable chameleons. That β-ketoester backbone? It’s precisely what enables its dual reactivity—dancing between ketone and enol chemistries with remarkable ease. Below is a consolidated technical profile drawn from your exhaustive dataset.

Core Identity & Properties

- Systematic Name: Ethyl acetoacetate
- Aliases:
  Acetoacetic ester, Ethyl acetylacetate, Ethyl 3-oxobutanoate
  Commercial Grades: Synthesis-grade / extra-pure EAA
- CAS Registry: 141-97-9
- Formula: C₆H₁₀O₃ | MW: 130.14 g/mol

This clear, nearly colorless liquid (APHA ≤20) handles routine storage below 30°C gracefully. Practitioners note its density hovers at 1.029 g/mL (20°C), with phase transitions from -43°C (melting) to 181°C (boiling). Its flash point of 185°F demands standard flammability precautions—hardly surprising given the energy in that carbonyl-enol tautomerism.

Reactivity Profile

The magic lies in EAA’s structural duality. Lab studies confirm its β-keto ester framework drives exceptional performance in:
- Condensation reactions (think Knoevenagel or Claisen)
- Cyclization cascades
- Heterocycle construction (pyrazoles, pyrimidines, etc.)
Its enol form’s nucleophilicity and ketone electrophilicity make it a true two-in-one synthon.

Sector-Specific Applications

Pharmaceuticals

EAA builds critical drug scaffolds:
- Analgesics/Antipyretics: Aminopyrine intermediates
- Cardiovascular: Pentoxifylline, Dipyridamole precursors
- Anticoagulants: 4-Hydroxycoumarin routes
- Antibiotics: Amoxicillin, Penicillin derivatives
- CNS Agents: Lobeline hydrochloride intermediates

Crop Science

Agrochemical manufacturers leverage EAA’s heterocycle-forming prowess for:
- Insecticides: Diazinon, Pyrifos cores
- Fungicides: Hymapropin, Sulimidine backbones
- Herbicides: Flavazole acetonicotinic acid synthesis
- Growth Regulators: Cintofen production

Flavor & Fragrance

GB 2760-96-approved for food aromas, EAA imparts:
- Fruit notes (apple, peach, cherry) in beverages
- Barrel-aged spirit accents (rum, whisky)
- Cosmetic depth in gardenia and berry accords

Color Chemistry

Dye labs exploit EAA for:
- Azo yellow pigments
- Hansa Yellow Lake intermediates via acetylacetylation
- Pyrazolone chromophores (condensation with arylhydrazines)

Analytical Science

Beyond synthesis, EAA serves as:
- GC stationary phase for C4-C6 isomer separation
- Chelation reagent for Fe³⁺, Tl⁺, Ca²⁺, Cu²⁺ detection

Industrial Processes

A versatile solvent/precursor for:
- Cellulose resin processing
- Polymer stabilizers
- Lactone/purine/pyridine heterocycle libraries

Why Chemists Reach for EAA

Field experience confirms it: few intermediates match ethyl acetoacetate’s balance of reactivity, safety, and cost-efficiency. Its chameleonic β-ketoester identity enables chemistry that’d otherwise require multiple specialized reagents. From crafting life-saving drugs to formulating orchard-saving pesticides, EAA remains a fixture on lab shelves worldwide—a testament to molecular versatility done right.