SYNTHESIS, CHARACTERIZATION AND CRYSTAL DENSITY MODELING OF 4 C24H28 CAGE-FUNCTIONALIZED ALKENES

Titanium-promoted reductive dimerization of methylated cyclo[5.4.0.0(2 ,6).0(3,10)-.0(5,9)]undecan-8-ones, 5a, 5b, and 8, afforded mixtures i n each case of ''methylated PCU alkene dimers'' (6a-d, 7a-d, and 9a, r espectively). Individual isomers have been isolated from these mixture s via column chromatography followed by multiple fractional recrystall ization of individual chromatography fractions. Structures of four iso merically pure C24H28 alkenes, i.e., 6c, 6d, 7c, and 9a have been esta blished unequivocally by application of single crystal X-ray crystallo graphic methods. The crystal density of each alkene (calculated from u nit cell parameters) is compared with the results of theoretical densi ty predictions.