Search results
Results From The WOW.Com Content Network
Cis-1,4-Di-tert-butylcyclohexane has an axial tert-butyl group in the chair conformation and conversion to the twist-boat conformation places both groups in more favorable equatorial positions. As a result, the twist-boat conformation is more stable by 0.47 kJ/mol (0.11 kcal/mol) at 125 K (−148 °C) as measured by NMR spectroscopy .
An example of interactions within a molecule that would lead to steric strain, leading to a shift in equilibrium from boat to chair, is the interaction between the two methyl groups in cis-1,4-dimethylcyclohexane.
A copper chromite catalyst is usually used industrially. [1] The cis/trans ratio of the CHDM is affected by the catalyst. [2] Byproduct of this process are 4-methylcyclohexanemethanol (CH 3 C 6 H 10 CH 2 OH) and the monoester methyl 4-methyl-4-cyclohexanecarboxylate (CH 3 C 6 H 10 CO 2 CH 3, CAS registry number 51181-40-9). [3]
Very often, cis–trans stereoisomers contain double bonds or ring structures. In both cases the rotation of bonds is restricted or prevented. [4] When the substituent groups are oriented in the same direction, the diastereomer is referred to as cis, whereas when the substituents are oriented in opposing directions, the diastereomer is referred to as trans.
a torsion angle between 0° and ±30° is called synperiplanar (sp), also called syn-or cis-conformation a torsion angle between 30° to 90° and −30° to −90° is called synclinal (sc), also called gauche or skew [ 34 ]
Most methylcyclohexane is extracted from petroleum but it can be also produced by catalytic hydrogenation of toluene: CH 3 C 6 H 5 + 3 H 2 → CH 3 C 6 H 11. The hydrocarbon is a minor component of automobile fuel, with its share in US gasoline varying between 0.3 and 1.7% in early 1990s [10] and 0.1 to 1% in 2011. [11]
A 4-ounce serving of chicken tenderloins provides 110 calories, 25 grams of protein and 1 gram of fat. Thigh.
If, in addition, the two carbons are different isotopes (say, 12 C and 13 C), there would be three distinct structural isotopomers, since 1-13 C-1,1-dideuteroethene would be different from 1-13 C-2,2-dideuteroethene. And, in both cases, the 1,2-dideutero structural isotopomer would occur as two stereoisotopomers, cis and trans.