title: Two diastereomers of (+-)-cis-2-(3-oxo-1,3,4,5,6, 7-hexahydroisobenzofuran-1-yl)cyclohexanecarboxylic acid
abstract: The structures are presented for both diastereomers of the title compound, C(15)H(20)O(4), produced by base-catalyzed self-condensation of cyclohexane-cis-1,2-dicarboxylic anhydride in refluxing triethylamine. Equilibration of either diastereomer under the condensation conditions yielded the same 5:3 mixture. In the crystal, one diastereomer, (II), is ordered, while the other, (I), displays both flexional ring disorder and carboxyl disorder; both aggregate as centrosymmetric hydrogen-bonded dimers [for (I), O.O = 2.680 (2) A; for (II), O.O = 2.635 (4) A].
authors.affiliation: Carl A. Olson Memorial Laboratories, Department of Chemistry, Rutgers University, Newark, NJ 07102, USA.
authors.initials: JM
authors.lastname: Newman
authors.initials: HW
authors.lastname: Thompson
authors.initials: RA
authors.lastname: Lalancette