1,2-benzisoxazol-3(2H)-one

Also known as: Benzo[d]isoxazol-3-ol, Benzo[d]isoxazol-3(2H)-one, 1,2-Benzisoxazol-3-ol, 1,2-Benzisoxazolin-3-one, 3-Hydroxy-1,2-benzisoxazole, 3-Hydroxybenzisoxazole, 1,2-Benzoxazol-3(2H)-one, 1,2-benzoxazol-3-ol, Buttpark 43\57-21, MFCD00125030

1,2-benzisoxazol-3(2H)-one (CAS 21725-69-9) is a compound in the Ketones category listed in the Jingsj chemical database. It has the molecular formula C7H5NO2 and a molecular weight of 135.120 g/mol. Key properties include a melting point of 140-142ºC, a boiling point of 299.9±13.0 °C at 760 mmHg, a density of 1.4±0.1 g/cm3 and a flash point of 135.2±19.8 °C. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.

CAS No.: 21725-69-9
Jingsj CID: J-1383557-9
Molecular Formula: C₇H₅NO₂
Molecular Weight: 135.120 g/mol
Category: Ketones
Last updated: 8/21/2026

Request MSDS / TDS

No offers for this compound yet.

Request a quote

Physicochemical Properties

Melting Point	140-142ºC
Boiling Point	299.9±13.0 °C at 760 mmHg
Density	1.4±0.1 g/cm3
Flash Point	135.2±19.8 °C
Exact Mass	135.032028
PSA	46.26000
LogP	0.89
Vapor Pressure	0.0±0.7 mmHg at 25°C
Refractive Index	1.664

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 1,2-benzisoxazol-3(2H)-one?

The CAS number of 1,2-benzisoxazol-3(2H)-one is 21725-69-9.

What are the molecular formula and molecular weight of 1,2-benzisoxazol-3(2H)-one?

1,2-benzisoxazol-3(2H)-one has molecular formula C7H5NO2 and molecular weight 135.120 g/mol.

What are the upstream and downstream products of 1,2-benzisoxazol-3(2H)-one?

For 1,2-benzisoxazol-3(2H)-one, Upstream Products: Salicylhydroxamic acid, Salicylic acid, Acetylsalicylic acid; Downstream Products: 3-(Piperazin-1-yl)-1,2-benzisoxazole, 5-Nitro-1,2-benzisoxazol-3(2H)-one, 5-Chloro-1,2-benzisoxazol-3(2H)-one.

Data compiled from public chemical databases such as PubChem and supplier catalogs; supplier offers are provided by suppliers.

Last updated: 8/21/2026

How to cite: Jingsj. "1,2-benzisoxazol-3(2H)-one (CAS 21725-69-9)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-1383557-9 (accessed 2026-11-09).

Data for reference only; verify product details with suppliers before purchase.