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CNDO/2 Calculations have been performed on the title compounds and on the anions derived from them. The results indicate that in the anion there is significant transannular transfer of charge to the 4-position. The amount of such transfer is effectively independent of the 4-substituent. It is concluded that the effect of the substituent upon the stability of the acid must be an important factor.  相似文献   

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CNDO/2 Calculations have been performed on the title compounds and on the anions derived from them. The results indicate that in the anion there is significant transannular transfer of charge to the 4-position. The amount of such transfer is effectively independent of the 4-substituent. It is concluded that the effect of the substituent upon the stability of the acid must be an important factor.  相似文献   

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The tetrahydropyranyl ether of 1-hydroxycyclopropanecarboxaldehyde, readily available from 1-hydroxycyclopropanecarboxylic acid, allows the preparation of functionalized 1-vinylcyclopropanols which undergo specific four- or five-membered ring annulations.  相似文献   

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The structures and relative energies of the conformers of phenylcyclohexane, and 1-methyl-1-phenylcyclohexane have been calculated at theoretical levels including HF/6-31G, B3LYP/6-311G, MP2/6-311G, MP2/6-311(2df,p), QCISD/6-311G, and QCISD/6-311G(2df,p). The latter gives conformational enthalpy (DeltaH degrees ), entropy (DeltaS degrees ), and free energy (DeltaG degrees ) values for phenylcyclohexane that are in excellent agreement with the experimental data. The calculations for 1-methyl-1-phenylcyclohexane find a free energy difference of 1.0 kcal/mol at -100 degrees C, favoring the conformation having an axial phenyl group, that is in only modest agreement with the experimental value of 0.32 +/- 0.04 kcal/mol. The origin of the phenyl rotational profiles for the conformers of phenylcyclohexane and 1-methyl-1-phenylcyclohexane is discussed.  相似文献   

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Ohne Zusammenfassung  相似文献   

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The radical polymerizations of 1-phthalimido-1,3-butadiene (1-PB) and 1-succinimido-1,3-butadiene (1-SB) were carried out in bulk and in solution. The polymers obtained had reduced viscosities in the ranges of 1.0–4.0 (1-PB) and 0.2–0.6 (1-SB). Both polymers had a similar softening point of 190–200°C. The radical polymerization of 1-phthalimido-1,3-butadiene clearly showed a tendency to give crosslinked polymer. Steric arguments about these polymer structures as a result of the infrared and ozonolysis data led to the conclusion that these polymers contained approximately 20% of the 3,4 form but no 1,2 configuration, and, therefore, that the 1,4 addition was preferred.  相似文献   

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