Stereochemistry of dihydroxylation of N-arylbicyclo[2.2.1]-hept-5-ene-endo- and -exo-2,3-dicarboximides
摘要:
Stereochemistry of the oxidation of N-arylbicyclo[2.2.1]hept-5-ene-endo-and-exo-2,3-dicarboximides at the double bond with peroxyacetic acid generated in situ in the presence of sulfuric acid and with an anhydrous dioxane solution of peroxyacetic acid was studied. In both cases, the reaction was stereospecific, regardless of the substituent in the N-aryl group and configuration of the imide ring, but the reaction direction depended on the presence of water in the system. In the first case, the corresponding trans-5,6-dihydroxy derivatives were formed, while in the second, exo-5,6-epoxy derivatives. The oxidation of N-arylbicyclo[2.2.1]-hept-5-ene-endo-and-exo-2,3-dicarboximides with a solution of potassium permanganate in aqueous acetone gave the corresponding N-aryl-cis-5,6-dihydroxybicyclo[2.2.1]heptane-endo-and-exo-2,3-dicarboximides. The exo,cis,exo and exo,cis,endo configurations of the synthesized compounds were determined by H-1 NMR spectroscopy.
Transition-State Stabilization by n→π* Interactions Measured Using Molecular Rotors
作者:Erik C. Vik、Ping Li、Perry J. Pellechia、Ken D. Shimizu
DOI:10.1021/jacs.9b08542
日期:2019.10.23
A series of 16 molecular rotors were synthesized to investigate the ability of n→π* interactions to stabilize transition states (TS) of bond rotation. Steric contributions to the rotational barrier were isolated using control rotors, which could not form n→π* interactions. Rotors with strong acceptor π* orbitals such as ketones, aldehydes, and nitriles had greatly increased rates of rotation. The TS
Spatial arrangement of norbornanedicarboxylic acids N-arylimides
作者:M. S. Salakhov、B. T. Bagmanov、N. S. Nabiev
DOI:10.1134/s1070428010110023
日期:2010.11
The effect of substituents on the spatial arrangement of norbornane compounds was investigated. Norbornanedicarboxylic acids N-arylimides with OCH(3), Cl, NO(2) groups in the ortho-position of the aromatic ring form as conformational isomers with hindered rotation. The specific spatial isomerism is confirmed by the quantum-chemical calculations.
SALAXOV M. S.; BAGMANOV B. T.; NAGIEV V. A., IN-T XLORORGAN. SINTEZA AN AZSSR, SUMGAIT,(1986) 12 S., IL., VINITI , 862+