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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
cis,cis,cis-tetramethyl 1,2,4,5-cyclohexanetetracarboxylate
1Department of Geology, Southern Illinois University-4324, Carbondale, IL 62901, USA. robinson@geo.siu.edu.
Abstract:
The title compound, C(14)H(20)O(8), was synthesized from the hydrogenation of tetramethyl 1,4-cyclohexadiene-1,2,4, 5-tetracarboxylate with a catalytic amount of palladium/carbon. All four carbonyl moieties of the methyl ester groups are on the same face of the chair-conformed ring. The substantial ring distortion associated with the 1,3-diaxial methoxycarbonyl substituents is reflected in the large difference between bond angles as well as torsion angles, respectively, that in undistorted cyclohexanes would be approximately the same.
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