Cis-1,4-dimethylcyclohexane

CIS 1 2 Dimethylcyclohexane trans 1 2 Dimethylcyclohexane Axial-equatorial Diequatorial (1248 3) (1246 8) (1 5) trans... 

Dimethylallyl diphosphate, biosynthesis of, 1077 geranio biosynthesis and. 382 cis-1,2-Dimethylcyclohexane. 

Common Name 1,2-ds-Dimethylcyclohexane Synonym cis-1,2-dimethylcyclohexane Chemical Name 1,2-c/A-di methyl cyclohexane CAS Registry No 2207-01-4 Molecular Formula C8H16 Molecular Weight 112.213 Melting Point (°C) ... 

DIMETHYLCYCLOHEXANE cis-1,2-DIMETHYLCYCLOHEXANE trans-1,2-DIMETHYLCYCLOHEXANE cis-1,3-DIMETHYLCYCLOHEXANE trans-1,3-DIMETHYLCYCLOHEXANE c i s-1,4-DIMETHYLCYCLOHEXANE trans-1,4-DIMETHYLCYCL0HEXANE ETHYLCYCLOHEXANE 2-ETHYL-1-HEXENE... 

Like the 1,4-dimethyl derivatives, trans-1,2-dimethylcyclohexane has a lower heat of combustion (see Table 3.2) and is more stable than cis-1,2-dimethylcyclohexane. The cis stereoisomer has two chair conformations of equal energy, each containing one axial and one equatorial methyl group. 

Draw the conformational isomers of cis-1,2-dimethylcyclohexane and cis-3,4-dimetliylcyclohexanone. While the cyclohexane conformers are of equal energy, the cyclohexanone conformers are not. Indicate which con-former is favored and explain why. 

A meso compound has stereocenters, but the compound also has symmetry that allows it to be the mirror image of itself. Consider cis-1,2-dimethylcyclohexane as an example. This molecule has a plane of symmetry cutting the molecule in half. Everything on the left side of the plane is mirrored by everything on the right side ... 

Construct cis- 1,2-dimethylcyclohexane by placing one —CH3 group axial and the other equatorial. Do ring flips and examine the two chair conformations. Which is the more stable conformation Explain your answer (11a). Given the two isomers, trans- 1,2-dimethylcyclohexane and cis- 1,2-dimethylcyclohexane, which is the more stable isomer Explain your answer (lib). 

In the case of the decalins, both rings assume chair conformations. For cz.v-decalin the carbons of the first ring are attached to an axial position and an equatorial position of the second ring, just like the methyl groups of cis-1,2-dimethylcyclohexane. Likewise, the carbons of the second ring are attached to an axial and an equatorial position of the first ring. A ring-flip, which interconverts axial and equatorial positions, can occur. 

Table 9. Stereochemistry of the insertion of photochemically generated cyanonitrene into tertiary C—H bonds of cis-1,2-dimethylcyclohexane 45>...

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