5231-87-8

Basic information

• Product Name: Diethyl squarate
• Synonyms: 3,4-DIETHOXY-3-CYCLOBUTENE-1,2-DIONE, 98 %;DiethylSquarate98%;3,4-DIETHOXYCYCLOBUTANE-1,2-DIONE;Diethyl squarate, Squaric acid diethyl ester;SQUARIC ACID DIETHYL ESTER,(DIETHYL SQUARATE, 3,4-DIETHOXY-3-CYCLOBUTENE-1,2-DIONE);DIETHOXYCYCLOBUTENEDIONE;3,4-DIETHOXY-3-CYCLOBUTENE-1,2-DIONE 98%;SQUARICACIDDIETHYLESTER/3,4-DIETHOXY-3-CYCLOBUTENE-1,2-DIONE
• CAS NO: 5231-87-8
• Molecular Formula: C₈H₁₀O₄
• Molecular Weight: 170.16
• Product Categories: Cyclobutanes & Cyclobutenes;Simple 4-Membered Ring Compounds;Ring Systems;Aluminium foil bag/Fluoride bottle or on your request
• Mol File: 5231-87-8.mol
• Article Data: 32

Chemical Properties

• Melting Point: 13-18 °C
• Boiling Point: 95 °C0.1 mm Hg(lit.)
• Flash Point: >230 °F
• Appearance: Clear yellow to light brownish/Liquid
• Density: 1.15 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.000226mmHg at 25°C
• Refractive Index: n20/D 1.509(lit.)
• Storage Temp.: 2-8°C
• Water Solubility: insoluble
• BRN: 640626
• CAS DataBase Reference: Diethyl squarate(CAS DataBase Reference)
• NIST Chemistry Reference: Diethyl squarate(5231-87-8)
• EPA Substance Registry System: Diethyl squarate(5231-87-8)

Safety Data

• Hazard Codes: Xn,Xi
• Statements: 36/37/38-42/43
• Safety Statements: 7-26-37/39-24-23
• WGK Germany: 3
• RTECS: GU1772466
• F: 10
• Hazardous Substances Data: 5231-87-8(Hazardous Substances Data)

Usage

Description

Diethyl squarate, also known as squaric acid diethyl ester, is a clear yellow to light brownish liquid that serves as an intermediate in the synthesis of various compounds and materials. It is formed through the reaction with glycosylamines, which are produced by reducing oligosaccharides. The resulting derivatives can be linked to amino-functionalized lipids, solids, or proteins.

Uses

Used in Pharmaceutical Industry:
Diethyl squarate is used as an intermediate for pharmaceutical products, playing a crucial role in the development and synthesis of various medications.
Used in Photochemical Industry:
Diethyl squarate is utilized as a photochemical intermediate, particularly in the dry-view process. It is also involved in the synthesis of photosensitive squaraine dyes, such as laser dyes used in CD-ROM technology.
Used in Synthesis of Furanones and Quinones:
3,4-Dethoxy-3-cyclobutene-1,2-dione, a derivative of diethyl squarate, is used as a starting material for the synthesis of furanones and quinones. It undergoes ethoxy substitution with amines and unsaturated organosilanes, which are essential in the production of these compounds.
Used in Synthesis of Functional Polymers:
Diethyl squarate serves as an intermediate in the synthesis of functional polymers, which have a wide range of applications in various industries due to their unique properties and functionalities.

InChI:InChI=1/C8H10O4/c1-3-11-7-5(9)6(10)8(7)12-4-2/h3-4H2,1-2H3

Upstream product

• 64-17-5 ethanol 
• 2892-51-5 squaric acid 
• 3200-96-2 2,3,4,4-tetrachloro-cyclobut-2-en-1-one 
• 122-51-0 orthoformic acid triethyl ester 
• 1007834-24-3 2,3-diethoxy-1,3-butadiene-1,4-dione 
• 61699-62-5 diisopropyl squarate 
• 79-37-8 oxalyl dichloride 

Downstream Products

• 29950-11-6 3-ethoxy-4-morpholinocyclobut-3-ene-1,2-dione 
• 61699-49-8 1,2-di-(2-phenylethyloxy)-cyclobutenedione 
• 131588-95-9 3-Ethoxy-4-<(2-hydroxy-1,1-dimethylethyl)amino>-3-cyclobutene-1,2-dione 
• 22118-95-2 3-ethoxy-4-phenyl-3-cyclobutylene-1,2-dione 
• 158599-29-2 2,3-diethoxy-4-hydroxy-4-phenyl-2-cyclobutenone 
• 102268-44-0 triphenylphosphoranylidenecylobutanetrione 
• 73279-58-0 3-Ethoxy-4-p-tolyl-3-cyclobuten-1,2-dion 
• 5222-73-1 3,4-dimethoxy-3-cyclobutene-1,2-dione 
• 131588-97-1 3-Ethoxy-4-<2-(4-hydroxyphenyl)ethylamino>-3-cyclobutene-1,2-dione 
• 147932-86-3 3-ethoxy-4-phenacylcyclobut-3-ene-1,2-dione 
• 131588-96-0 3-Ethoxy-4-<(1R)-(1-ethyl-2-hydroxyethyl)amino>-3-cyclobutene-1,2-dione 
• 21619-12-5 3-ethoxy-4-(2-oxocyclohexyl)cyclobut-3-ene-1,2-dione 
• 131589-03-2 3-Ethoxy-4-<(1'S,2'R)-(2'-hydroxy-1'-methyl-2'-phenylethyl)(methyl)amino>-3-cyclobutene-1,2-dione 
• 131589-09-8 3,4-Bis<(1'S,2'R)-(2'-hydroxy-1'-methyl-2'-phenylethyl)(methyl)amino>-3-cyclobutene-1,2-dione 

Relevant articles and documents

An Unsymmetrical Squaraine-Based Activatable Probe for Imaging Lymphatic Metastasis by Responding to Tumor Hypoxia with MSOT and Aggregation-Enhanced Fluorescent Imaging

Optoacoustic imaging has great potential for preclinical research and clinical practice, and designing robust activatable optoacoustic probes for specific diseases is beneficial for its further development. Herein, an activatable probe has been developed for tumor hypoxia imaging. For this probe, indole and quinoline were linked on each side of an oxocyclobutenolate core to form an unsymmetrical squaraine. A triarylamine group was incorporated to endow the molecule with the aggregation enhanced emission (AEE) properties. In aqueous media, the squaraine chromophore aggregates into the nanoprobe, which specifically responds to nitroreductase and produces strong optoacoustic signals due to its high extinction coefficient, as well as prominent fluorescence emission as a result of its AEE feature. The nanoprobe was used to image tumor metastasis via the lymphatic system both optoacoustically and fluorescently. Moreover, both the fluorescence signals and three-dimensional multispectral optoacoustic tomography signals from the activated nanoprobe allow us to locate the tumor site and to map the metastatic route.

Multiple linker half-squarylium dyes for dye-sensitized solar cells; Are two linkers better than one?

The synthesis and full characterization of new half-squaraine dyes (Hf-SQ) containing two or three carboxylate-based linker units is reported and these dyes tested in dye-sensitized solar cell (DSC) devices. The data show improved device efficiency for a Hf-SQ dye with two linkers (η = 5.5%) compared to the highest efficiency Hf-SQ previously reported which had only a single linker (η = 5.0%); this is mainly due to improved Voc. To understand the effects of using multiple dye linker groups, device I-V data have been correlated with single crystal X-ray structural analysis and dye electrical properties (both in solution and adsorbed to TiO2) using UV-visible and ATR-IR spectroscopy along with cyclic voltammetry, and also theoretical studies using density functional theory (DFT) calculations. These data show that positioning the linkers near the dye LUMO and so that this enables complete linker chemisorption are key factors for device performance.

Novel bisubstrate uridine-peptide analogues bearing a pyrophosphate bioisostere as inhibitors of human O-GlcNAc transferase

Protein O-linked β-D-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation), an essential post-translational as well as cotranslational modification, is the attachment of β-D-N-acetylglucosamine to serine and threonine residues of nucleocytoplasmic proteins. An aberrant O-GlcNAc profile on certain proteins has been implicated in metabolic diseases such as diabetes and cancer. Inhibitors of O-GlcNAc transferase (OGT) are valuable tools to study the cell biology of protein O-GlcNAc modification. In this study we report novel uridine-peptide conjugate molecules composed of an acceptor peptide covalently linked to a catalytically inactive donor substrate analogue that bears a pyrophosphate bioisostere and explore their inhibitory activities against OGT by a radioactive hOGT assay. Further, we investigate the structural basis of their activities via molecular modelling, explaining their lack of potency towards OGT inhibition.

Carboxyl-modified near-infrared squaric acid dye as well as preparation method and application thereof

The invention discloses a carboxyl-modified near-infrared squaric acid dye as well as a preparation method and application thereof. The carboxyl-modified near-infrared squaric acid dye is prepared by taking a carboxyl-modified 2-methylbenzothiazole derivative and a dicyanovinyl squaric acid derivative as raw materials. The near-infrared squaric acid dye has relatively good stability and excellent optical performance, and particularly, the water solubility of the dye can be enhanced by carboxylic acid groups. When the near-infrared squaric acid dye is used for detecting parallel and mixed G-quadruplex, the G-quadruplex can interact with dye molecules, and a dye absorption spectrum and a fluorescence emission spectrum are changed while the topological structure of the G-quadruplex is not changed, so that the near-infrared squaric acid dye can be used as a fluorescent probe for detecting the parallel and mixed G-quadruplex.