![Molecular structure of Thieno[2,3-b]thiophene (CAS 250-84-0)](/images/chem_structures_svg/275/250-84-0.svg)
Thieno[2,3-b]thiophene
Also known as: 1,6-Dithiapentalene, 1,6-Thiophthene, Polythieno[2,3-b]thiophene, Thiophthene
Thieno[2,3-b]thiophene (CAS 250-84-0) is a compound in the Pharma Intermediates category listed in the Jingsj chemical database. It has the molecular formula C6H4S2 and a molecular weight of 140.226 g/mol. Key properties include a melting point of 7 °C, a boiling point of 225.9±13.0 °C at 760 mmHg, a density of 1.4±0.1 g/cm3 and a flash point of 64.3±6.0 °C. It is classified under GHS with signal word Warning and hazard statements H302 — Harmful if swallowed, H315 — Causes skin irritation and H319 — Causes serious eye irritation. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.
- CAS No.
- 250-84-0
- Jingsj CID
- J-1497879-1
- Molecular Formula
- C6H4S2
- Molecular Weight
- 140.226 g/mol
- Category
- Pharma Intermediates
- Last updated
- 8/21/2026
No offers for this compound yet.
Request a quotePhysicochemical Properties
| Melting Point | 7 °C |
|---|---|
| Boiling Point | 225.9±13.0 °C at 760 mmHg |
| Density | 1.4±0.1 g/cm3 |
| Flash Point | 64.3±6.0 °C |
| Exact Mass | 139.975433 |
| PSA | 56.48000 |
| LogP | 5.31 |
| Vapor Pressure | 0.1±0.4 mmHg at 25°C |
| Refractive Index | 1.729 |
GHS Safety & Compliance
- H302 — Harmful if swallowed
- H315 — Causes skin irritation
- H319 — Causes serious eye irritation
- H335 — May cause respiratory irritation
Customs & Trade Information
| HS Code | 2934999090 |
|---|---|
| Summary | 2934999090. other heterocyclic compounds. VAT:17.0%. Tax rebate rate:13.0%. . MFN tariff:6.5%. General tariff:20.0% |
Frequently Asked Questions
What is the CAS number of Thieno[2,3-b]thiophene?
The CAS number of Thieno[2,3-b]thiophene is 250-84-0.
What are the molecular formula and molecular weight of Thieno[2,3-b]thiophene?
Thieno[2,3-b]thiophene has molecular formula C6H4S2 and molecular weight 140.226 g/mol.
Is Thieno[2,3-b]thiophene hazardous?
Thieno[2,3-b]thiophene has GHS signal word Warning and hazard statements H302 — Harmful if swallowed; H315 — Causes skin irritation; H319 — Causes serious eye irritation.
Data compiled from public chemical databases such as PubChem and supplier catalogs; supplier offers are provided by suppliers.
Last updated:
How to cite: Jingsj. "Thieno[2,3-b]thiophene (CAS 250-84-0)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-1497879-1 (accessed 2026-11-09).
Data for reference only; verify product details with suppliers before purchase.