36mined in a like manner with A = 4 mm and B = 4 mm. Other diffractometer parameters and the method of estimation of standard deviations have been described previously.10 As a check on the stability of the instrument and the crystal, two reflections, the (200) and (002), were measured after every 30 reflections; no significant variation was noted.One independent quadrant of data was measured out to 28 = 1 10"; a total of 349 unique reflections ( I > 2 4 ) ) was obtained.The intensities were corrected for Lorentz and polarization effects but not for absorption, since the extreme values of the transmission factors were 0.90 and 0.95. The full-matrix. least-squares refinement was carried out using the Busing and Levy program O R F L S .~~ The function w(lF,l -I F c ( ) l 3 was minimized. No corrections were made for extinction or anomalous dispersion. Neutral atom scattering factors were taken from the compilations of Cromer and Waberl4 for C and N: those for hydrogen were from "International Tables for X-ray Crystallography." Final bond distances. angles, and errors were computed with the aid of the Busing, Martin, and Levy ORFFE program.16 Crystal structure illustrations were obtained with the program ORTEP.~' Fourier calculations were made with the A L F F~~ program. ~ ~~ Abstract:The formation and characterization of the first x complexes observed between ozone and aromatic or olefinic x systems are described. A correlation was made between the ionization potentials of a group of aromatic substrates and the wavelength of the absorption of their ozone complexes in the visible region. Two of the complexes were allowed to react with certain cis and trans olefins. The cis-trans ratios of the ozonides produced were different from those of the ozonides obtained by ozone alone in the cases of the cis-and rrans-l,2-diisopropylethylenes. However, there was no appreciable difference in the results obtained using complexed or uncomplexed ozone with the less bulky cis-and trans-3-hexenes.
Contrary to previous reports cyclohexanone and pinacolone are not oxidized to the corresponding Baeyer–Villiger oxidation products during ozonolysis of ethylidenecyclohexane in their presence. Addition of propionaldehyde to a solution of the 1,2,3-trioxolane initial ozonide of trans-1,2-di-t-butylethylene resulted in oxidation of the aldehyde to propionic acid and reduction of the 1,2,3-trioxolane to pivaldehyde. Thus, there is no necessity for the four-membered Staudinger molozonide as an ozonolysis intermediate, as recently proposed by Story.
may be attributed to intervention by a complex such as 11.Thus it appears that the dependence of the isomeric composition of the product mixture obtained by reduction of 3,3,5-trimethylcyclohexanone or 4-tertbutylcyclohexanone with TIBA cannot be attributed to a single cause. At least three minor factors are operative: isomeric equilibration via a Meerwein-Ponndorf-Verley type reduction, association of the reducing agent, and complexation of TIBA by the initially formed aluminum alkoxide. Greatest selectivity is attained when TIBA is employed in excess and the reduction is performed in concentrated solution. Experimental SectionManipulations of air-sensitive compounds were performed either in a Kewaunee inert atmosphere box or by employing special bench-top techniques.17 Reagents were transferred in flame-dried syringes which were cooled under nitrogen. Products were analyzed by glc utilizing a 20-ft column packed with 5% Carbowax 20M on Chromosorb G and a Hewlett-Packard Model 700 chromatograph. Ethyl benzoate was employed as internal standard in reduction of 3,3,5-trimethylcyclohexanone, and analyses were performed at 135°. Retention times for ketone, axial alcohol, and equatorial alcohol were 16.0, 25.2, and 31.1 min, respectively. For reduction of 4-ieri-butylcyclohexanone, 3,3,5-trimethylcyclohexanone was used as internal standard and analyses were performed at 150°. Retention times for ketone, axial alcohol, and equatorial alcohol were 22.6, 25.9, and 31.0 min, respectively.Materials.-Reagent-grade ether and benzene were refluxed for 24 hr over LiAlH, and NaAlH,, respectively, distilled through a 3-ft Vigreux column, and stored over sodium-lead alloy (J. T. Baker dri-Na) in a nitrogen atmosphere. Standard solutions of (17) D. F. Shriver, "The Manipulation of Air-Sensitive Compounds," McGraw-Hill, New York, N. Y. 1969.
Es werden die Bildung von π‐Komplexen zwischen Ozon und aromatischen bzw. olefinischen Bindungen wie z.B. im aromatischen Olefin (I), Mesitylphenyläthan, Hexaäthylbenzol oder o‐Xylol beobachet und das Ionisationspotential der aromatischen Verbindung mit der Wellenlänge der Absorption des rr‐Komplexes im sichtbaren Bereich korreliert.
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