Ein Vielkomponentengemisch ges?ttigter und unges?ttigter Kohlenwasserstoffe

Ohne Zusammenfassung     

Lösungsmitteleffekte in Kernresonanzspektren gesättigter Kohlenwasserstoffe

Proton NMR solvent effects ν(CCl₄) – ν(C₆H₆) have been measured for the methyl groups in 25 saturated cycloalkanes. Magnitude and sign of the Δ values are correlated with the molecular shape. The results are discussed with particular respect to stereochemistry, and they provide a new method for distinguishing between geometrical isomers.     

Protonenresonanz-Spektroskopie ungesättigter Ringsysteme—XVI 7,7-Difluor-benzo-cyclopropen

The NMR-spectrum of 7·7-difluoro-benzo-cyclopropene ( 2 ) has been analysed to obtain chemical shifts and spin, spin-coupling constants: δ_AA′ = 7·6026, δ_BB′ = 7·4834 ppm; J_AB = 6·86, J_AA′ = 7·45, J_AB′ = 0·34 and J_BB′ = 1·89 Hz. Heteronuclear double resonance experiments have been used to establish a positive sign for ⁴J(H? F) (3.64 Hz) and a negative sign for ⁵J(H? F) (?0·33 Hz) in this molecule. The results are discussed with reference to the structure of 2 and the NMR data found for benzo-cyclopropene.     

Temperaturverhalten des Circulardichroismus und Konformationsanalyse einiger nichtkonjungierter ungesättigter Oxoverbindungen,und auf dem Steroid-Symposium in Mailand,Mai 1966

– The circular dichroism of some non-conjugated unsaturated carbonyl compounds, which are conformationally mobile, has been measured at +20° and at about ?178°. Specifically for the steroidal compounds 1 and 2 and the monocyclic aldehyde 14, their substituted analogs 4–6, 9–11, and 15–19, respectively, as well as for the aliphatic ketone 21 the CD. temperature gradients are interpreted in terms of the preferred conformations. In the case of the β,γ-unsaturated aldehydes 1 and 14, a correlation of these results with the photolytic decarbonylation from the excited singlet states is discussed.     

Lösungsmitteleffekte in Kernresonanzspektren gesättigter Kohlenwasserstoffe (III). Unterscheidung unpolarer und polarer Effekte bei Steroiden

Benzene-induced proton NMR. solvent shifts of methyl and methylene groups in 25 acyclic and cyclic saturated hydrocarbons have been studied. The dependence of magnitude and sign of these unpolar effects upon the molecular shape is again demonstrated. Solvent shifts in polar solutes (hydroxy- and keto-steroids) are shown to originate from a superposition of polar and unpolar effects. The implications for the interpretation of small solvent shifts in polar solutes are discussed.