Ethyl 5-oxo-2,3-diphenylcyclopentane-1-carboxylate

The title compound, C20H20O3, was prepared by an acyl-oin-type condensation reaction in the presence of sodium sand and dry ether using ethyl cinnamate as the starting material. The C - O bond lengths for the carbonyl groups are 1.191 (2) and 1.198 (2) Å, while the C - O bond in the ester group is 1.335 (2) Å. The C - C bond lengths in the phenyl groups average 1.375 Å, while the C - C bonds in the cyclo-penta-none ring average 1.525 Å, indicating single C - C bonds in the latter. © 2010.