Recommanded Product: 2,4-Dimethylpyridine, Chemistry involves the study of all things chemical – chemical processes, chemical compositions and chemical manipulation – in order to better understand the way in which materials are structured, how they change and how they react in certain situations. 108-47-4, Name is 2,4-Dimethylpyridine, molecular formula is C7H9N. In a article，once mentioned of 108-47-4
A 13C DNMR study of meso-1,1-bi(2-methylpiperidine) (7), meso-1,1′-bi(cis-2,4-dimethylpiperidine) (8), and meso-1,1′-bi(cis-4-tert-butyl-2-methylpiperidine) (9) with the aid of molecular mechanics calculation of the corresponding hydrocarbons 1,1′-bi(2-methylcyclohexane) (14), 1,1′-bi(cis-2,4-dimethylcyclohexane) (15), and 1,1′-bi(cis-4-tert-butyl-2-methylcyclohexane) (16) is reported.The most stable conformations of the bipiperidines are the enantiomeric conformations in which the lone pairs of the nitrogen atoms are approximately gauche to each other.In these conformations the N-N bond and all of the alkyl groups are equatorial to each of the chair-form piperidine rings.The energy barriers (DeltaG*) to the interconversion between these enantiomeric gauche conformations in 7, 8, and 9 are 12.5(-25 deg C), 17.7(+72 deg C), and 19.0 kcal mol-1 (+97 deg C), respectively.While the barrier for 7 is assigned to the passing inversion of the nitrogen atoms, the barriers for 8 and 9 are assigned to the single-passing rotation about the N-N bond.In the case of 7, the next stable conformations, in which one of the methyl groups is axial, were observed at the lower temperatures.The free energy difference between the next stable and the most stable conformations is 0.55 kcal mol-1 at -117 deg C, and the energy barrier between these conformations is 9.2 kcal mol-1 at -82 deg C, which is assigned to the ring inversion.
Consequently, the presence of a catalyst will permit a system to reach equilibrium more quickly, but it has no effect on the position of the equilibrium as reflected in the value of its equilibrium constant. I hope my blog about 108-47-4 is helpful to your research. Recommanded Product: 2,4-Dimethylpyridine
Reference：
Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis—I. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis