| Melting Point | 242°C (dec.) (lit.) |
| Color | White-Yellow |
| Linear Formula | C4H4(CO2H)4 |
| Formula Weight | 232.14 |
| Physical Form | Crystal-Powder at 20°C |
| Chemical Name or Material | Cyclobutane-1,2,3,4-tetracarboxylic acid |
| Molecular Weight | 232.14 g/mol |
| SMILES String | OC(=O)C1C(C(C1C(O)=O)C(O)=O)C(O)=O |
| Assay | 98% |
| Solubility | Methanol: soluble 10 mg/mL, clear, colourless to light yellow |
| CAS Number | 53159-92-5 |
| Empirical Formula | C8H8O8 |
| NACRES | NA.22 |
| PubChem Substance ID | 24859481 |
| UNSPSC Code | 12352100 |
| MDL Number | MFCD00013270 |
| InChI | 1S/C8H8O8/c9-5(10)1-2(6(11)12)4(8(15)16)3(1)7(13)14/h1-4H,(H,9,10)(H,11,12)(H,13,14)(H,15,16) |
| InChI Key | CURBACXRQKTCKZ-UHFFFAOYSA-N |
| PubChem CID | 266034 |
| Quality Level | 100 |
| Functional Groups | Carboxylic acid (four) |
| Form | Solid (white to pale yellow crystal-powder) |
CBTA is a four-membered carbocycle with a carboxyl group on every ring carbon. The formula is C8H8O8 and the molecular weight is 232.14 g/mol. The ring is strained and rigid, which is why polymers made from it are stiff and, because it is saturated, colourless: there is no extended π-conjugation to absorb visible light. The ring carbons are stereocentres, and several stereoisomers exist (all-cis, cis–trans–cis and others); the CAS number 53159-92-5 is listed without a stereodescriptor, and the isomer present influences the dianhydride route and the polymer properties.
Polymer chemists buy the acid, or its dianhydride, as the alicyclic counterpart of aromatic dianhydrides such as pyromellitic dianhydride: polyimides from CBDA are transparent where aromatic polyimides are yellow to brown. Materials chemists also use the tetra-acid as a rigid multidentate ligand for coordination polymers and as a capping agent for metal nanoparticles.
The grade offered is 98% assay. Ask for the Certificate of Analysis of the lot, and tell us the stereoisomer composition and water content you need if the acid will be converted to the dianhydride, because these influence the ring-closure and the polymer colour. Store in a tightly closed container in a cool, dry place. The powder is an irritant: use gloves, eye protection and a dust mask. The dianhydride (CBDA) is a separate product with a different CAS number.
Avoid breathing dust, use in a ventilated area or fume hood, and wash hands thoroughly after handling.
