4,4-Dimethyl-3,5,8-trioxabicyclo[5.1.0]octane

About This Product

4,4-Dimethyl-3,5,8-trioxabicyclo[5.1.0]octane has the formula C7H12O3, molecular weight 144.2 and CAS number 57280-22-5. It is a colourless to pale yellow clear liquid: the epoxide of 2,2-dimethyl-4,7-dihydro-1,3-dioxepine, which is cis-2-butene-1,4-diol protected as its acetone ketal. The molecule packs three future hydroxyl groups into a compact, reactive form. Two are masked as the acetonide and the third is latent in the strained epoxide ring, so when a nucleophile such as a ring nitrogen of cyclen or DO3A opens the epoxide, and the acetonide is later removed with acid, the product carries a 2,3-dihydroxy-1-(hydroxymethyl)propyl group. That is exactly the side chain of gadobutrol, which is why this epoxide is a core raw material of that contrast agent. Being a meso compound, it is also a standard substrate in asymmetric catalysis for desymmetrising ring-opening reactions, including carbon dioxide-mediated routes to chiral carbamates. Water, limited to 1.0 percent, and single impurities, below 0.05 percent, are the specification points, because water competes as a nucleophile and opens the ring to a diol. It is used as the side-chain building block in gadobutrol manufacture, in the synthesis of other protected triol and aminodiol intermediates, and as a meso-epoxide substrate in asymmetric catalysis research. Bio Green Chem supplies this epoxide at 98, 99 and 99.9 percent purity to specification on appearance, water, purity and largest single impurity, in drums or bulk. Regulatory documentation for pharmaceutical use is confirmed at enquiry.