5. (36 points) For each substituted cyclohexane: i) Indicate whether the compound given is a cis or trans isomer ii) Draw its ring-flip conformation (chairs have been provided) iii) Calculate the amount of energy in each and if possible state which one is more stable. YOU CAN PRINT OUT THESE PAGES AND SUBMIT THEM AS PART OF YOUR ASSIGNMENT SO YOU DON'T HAVE TO DRAW THE "CHAIRS" A) CH31 CH3 -CH3 B) CH3. CH3 CH3

87. Subject  :- Chemistry

Consider 1,2-dimethylcyclohexane.Q: Draw the two possible chair conformations for the trans isomer. Whichconformation, if either, is more stable?

Which of the following is the correct Newman projection for the following compound as viewed down the indicated bond in the conformation shown?" Br H CI 00000 ==>> CH₂ Br 11 H. CH₂ Br ||| CH₂ H IV CH₂ Br CH₂

4. (a) Draw a skeletal (line-bond) structure for 3,4-dimethylhexane. (b) Draw a sawhorse representation of any staggered conformation of this molecule looking down the carbon-3 to carbon-4 bond. (c) Draw a Newman projection looking down the carbon-3 to carbon-4 bond of the same conformation that you drew as a sawhorse representation.

Draw alternative chair conformations for the following substituted cyclohexane and determine which chair is more stable. C HO H ОН In its most stable chair conformation, indicate the orientation of each of the labeled groups in this substituted cyclohexane. Group a: Group b: Group c:

In the most stable chair conformation of the cyclohexane below, how many methyl groups would be axial? CH3 CH3 three zero two all four CH3 CH3

Which of the following is an accurate conformational drawing for compound Z? Z

Draw the two chair conformations of the following substituted cyclohexanes. In each case, label the more stable conformation.(a) cis-1-ethyl-2-methylcyclohexane

According to the following structure, draw the Newmann projections in which you must indicate: a) the most stable conformation and explain why it is more stable, b) the least stable conformation and explain why; c) a conformation where there is a gauche interaction.