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377406

Sigma-Aldrich

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

99%

Synonym(s):

Dimethyl squarate

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About This Item

Linear Formula:
(CH3O)2C4(=O)2
CAS Number:
5222-73-1
Molecular Weight:
142.11
MDL number:
MFCD00101316
UNSPSC Code:
12352100
PubChem Substance ID:
24863502
NACRES:
NA.22

Quality Level

100

Assay

99%

form

solid

mp

55-57 °C (lit.)

functional group

ether
ketone

storage temp.

2-8°C

SMILES string

COC1=C(OC)C(=O)C1=O

InChI

1S/C6H6O4/c1-9-5-3(7)4(8)6(5)10-2/h1-2H3

InChI key

SZBNZTGCAMLMJY-UHFFFAOYSA-N

Related Categories

General description

3,4-Dimethoxy-3-cyclobutene-1,2-dione (Dimethyl squarate) is a cyclobutene derivative. It reacts with hydroxylamine derivatives to afford 3-hydroxyamino-4-methoxy-3-cyclobutene-1,2-diones.

Application

3,4-Dimethoxy-3-cyclobutene-1,2-dione (Dimethyl squarate) may be used in the synthesis of the following compounds:
  • chiral squaramides, highly enantioselective catalyst for the Friedel-Crafts reactions of indoles
  • 3-(hydroxyamino)-4-methoxy-3-cyclobutene-1,2-dione
  • squarate derivatives of the O-SP-core antigens
  • methyl squarate derivative of the Ogawa O-SP-core antigen
  • o-quinodimethanes
  • benzocyclobutenes
  • quinones

Pictograms

Health hazard
GHS08

Signal Word

Danger

Hazard Statements

H317,H334

Precautionary Statements

P261 - P280 - P342 + P311

Hazard Classifications

Resp. Sens. 1 - Skin Sens. 1

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Regulatory Listings

Regulatory Listings are mainly provided for chemical products. Only limited information can be provided here for non-chemical products. No entry means none of the components are listed. It is the user’s obligation to ensure the safe and legal use of the product.

JAN Code

377406-VAR:
377406-5G:
377406-BULK:
377406-1G:

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Certificates of Analysis (COA)

Lot/Batch Number
MKCQ0903
MKCF5357
MKBR4150V
MKBK0489V
MKBB0097V

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Peng Xu et al.
Bioconjugate chemistry, 22(10), 2179-2185 (2011-09-09)
Bacterial O-SP-core antigens can be conjugated to proteins in the same, simple way as synthetic, linker-equipped carbohydrates by applying squaric acid chemistry. Introduction of spacers (linkers) to either O-SP-core antigens or protein carriers, which is involved in commonly applied protocols
Kerriann K Badal et al.
Cell reports, 26(3), 507-517 (2019-01-17)
Mechanisms that regulate the bi-directional transport of mitochondria in neurons for maintaining functional synaptic connections are poorly understood. Here, we show that in the pre-synaptic sensory neurons of the Aplysia gill withdrawal reflex, the formation of functional synapses leads to
Hydroxylamin-Derivate der Quadratsaure.
Zinner G, et al.
Arch. Pharm. (Weinheim), 318(11), 977-983 (1985)
The Journal of Organic Chemistry, 57, 6896-6896 (1992)
Tetrahedron Letters, 34, 6177-6177 (1993)
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