2-Butynoic acid
Also known as: Tetrolic acid, 1-Propynecarboxylic acid, 3-Methylpropiolic acid, But-2-ynoic acid, Methylacetylenecarboxylic acid
2-Butynoic acid (CAS 590-93-2) is a compound in the Organic Acids category listed in the Jingsj chemical database. It has the molecular formula C4H4O2 and a molecular weight of 84.073 g/mol. Key properties include a melting point of 78-80 °C(lit.), a boiling point of 203.0±9.0 °C at 760 mmHg, a density of 1.2±0.1 g/cm3 and a flash point of 90.9±15.2 °C. It is classified under GHS with signal word Danger and hazard statements H314 — Causes severe skin burns and eye damage. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.
- CAS No.
- 590-93-2
- Jingsj CID
- J-5286-8
- Molecular Formula
- C4H4O2
- Molecular Weight
- 84.073 g/mol
- Category
- Organic Acids
- Last updated
- 8/21/2026
No offers for this compound yet.
Request a quotePhysicochemical Properties
| Melting Point | 78-80 °C(lit.) |
|---|---|
| Boiling Point | 203.0±9.0 °C at 760 mmHg |
| Density | 1.2±0.1 g/cm3 |
| Flash Point | 90.9±15.2 °C |
| Exact Mass | 84.021126 |
| PSA | 37.30000 |
| LogP | 0.85 |
| Vapor Pressure | 0.1±0.8 mmHg at 25°C |
| Refractive Index | 1.468 |
| Storage Conditions | 2-8°C |
GHS Safety & Compliance
- H314 — Causes severe skin burns and eye damage
Customs & Trade Information
| HS Code | 2916190090 |
|---|---|
| Summary | 2916190090 unsaturated acyclic monocarboxylic acids, their anhydrides, halides, peroxides, peroxyacids and their derivatives。supervision conditions:AB(certificate of inspection for goods inward,certificate of inspection for goods outward)。VAT:17.0%。tax rebate rate:9.0%。MFN tariff:6.5%。general tariff:30.0% |
Frequently Asked Questions
What is the CAS number of 2-Butynoic acid?
The CAS number of 2-Butynoic acid is 590-93-2.
What are the molecular formula and molecular weight of 2-Butynoic acid?
2-Butynoic acid has molecular formula C4H4O2 and molecular weight 84.073 g/mol.
Is 2-Butynoic acid hazardous?
2-Butynoic acid has GHS signal word Danger and hazard statements H314 — Causes severe skin burns and eye damage.
What are the upstream and downstream products of 2-Butynoic acid?
For 2-Butynoic acid, Upstream Products: 2-Butyn-1-ol, Carbon dioxide, Propyne; Downstream Products: 2,3-dibromobutyric acid, 1-Benzyl-5-methyl-1H-1,2,3-triazole-4-carboxylic acid, 3-Methyl-3-pyrazolin-5-one.
Data compiled from public chemical databases such as PubChem and supplier catalogs; supplier offers are provided by suppliers.
Last updated:
How to cite: Jingsj. "2-Butynoic acid (CAS 590-93-2)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-5286-8 (accessed 2026-11-09).
Data for reference only; verify product details with suppliers before purchase.