Skip to Content
Merck
All Photos(1)

Key Documents

View All Documentation

123447

Sigma-Aldrich

3,4-Dihydroxy-3-cyclobutene-1,2-dione

≥99.0% (HPLC)

Synonym(s):

Squaric acid

Sign Into View Organizational & Contract Pricing
All Photos(1)

About This Item

Linear Formula:
(HO)2C4(=O)2
CAS Number:
2892-51-5
Molecular Weight:
114.06
Beilstein:
774275
EC Number:
220-761-4
MDL number:
MFCD00001334
UNSPSC Code:
12352103
PubChem Substance ID:
24847567
NACRES:
NA.23

Assay

≥99.0% (HPLC)

form

solid

mp

>300 °C (lit.)

SMILES string

OC1=C(O)C(=O)C1=O

InChI

1S/C4H2O4/c5-1-2(6)4(8)3(1)7/h5-6H

InChI key

PWEBUXCTKOWPCW-UHFFFAOYSA-N

Looking for similar products? Visit Product Comparison Guide

Related Categories

General description

3,4-dihydroxy-3-cyclobutene-1,2 dione, commonly known as squaric acid, is widely used in bioorganic and medicinal chemistry. It is an inhibitor of glyoxylase, semiqauric acid, pyruvate dehrogenase, and transketolase. It is used as a replacement for phosphate in a peptide-based ligand for an SH2 domain. Its derivatives are high-affinity ligands for excitatory amino acid receptors. These derivatives are also used as dyes for fluorescence detection of small biological molecules.

Application

3,4-Dihydroxy-3-cyclobutene-1,2-dione can be used:
  • In fluorescence detection in immunoassays, hybridization assays, enzymatic reactions, and other analytical procedures.
  • To form diffraction quality crystals.
  • To synthesize a squarate dianion, which is used as a building block to create uncharged polymeric networks. These ordered structures are used in catalysis, nonlinear optics, electrical conductivity, molecular recognition, and molecular sieves.

Pictograms

Corrosion
GHS05

Signal Word

Danger

Hazard Statements

H314

Hazard Classifications

Eye Dam. 1 - Skin Corr. 1B

Storage Class Code

8A - Combustible corrosive hazardous materials

WGK

WGK 3

Flash Point(F)

374.0 °F

Flash Point(C)

190 °C

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Find documentation for the products that you have recently purchased in the Document Library.

Visit the Document Library

Igor Bensemann et al.
Organic & biomolecular chemistry, 1(8), 1425-1434 (2003-08-22)
The preparation and crystal structures of fourteen complexes of N,N'-bis(2-pyridyl)aryldiamines with dicarboxylic acids and two complexes with squaric acid are reported. The recognition between the carboxylic acids and the 2-aminopyridine units occurs through the formation of the cyclic R(2)2 (8)
Construction of a 3D array of cadmium (ii) using squarate as a building block.
Maji, Tapas Kumar, et al.
CrystEngComm, 155-158 (2001)
Tetrahedron Letters, 48, 3595-3595 (2007)
M Burak Onaran et al.
The Journal of organic chemistry, 70(26), 10792-10802 (2005-12-17)
[structure: see text] A series of squaric acid-peptide conjugates were synthesized and evaluated as inhibitors of MMP-1. The cyclobut-3-enedione core was substituted at the 3-position with several functional groups, such as -N(alkyl)OH, -NHOH, and -OH, that are designed to bind
Elena Sanna et al.
Organic letters, 12(17), 3840-3843 (2010-08-10)
A minimalist squaramide-based chemodosimeter for Cu(2+) is described. Upon selective chelation to 2, Cu(2+) induces the formation of a highly colored zwitterionic radical, which is kinetically stable for hours. The presence of a radical is confirmed by EPR and ESI-MS.
View All Related Papers

Articles

Progress for High Performance Tandem Organic Solar Cells

Professor Chen (Nankai University, China) and his team explain the strategies behind their recent record-breaking organic solar cells, reaching a power conversion efficiency of 17.3%.

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service