XIX. Draw the ring flip for compound A and label compound B. Calculate and compare the energies of the two conformers (A and B respectively), knowing that a methyl-methyl gauche interaction is 3.8 kJ/mol, the H-CH3 diaxial interaction is 3.75 kJ/mol and the CH3 - CH3 diaxial interaction is 15 kJ/mol. Which isomer is more stable? H3C 5 6 Iz 2 CH3 4 CH3 A CH3 B

6) Place a circle around the molecules below that are enantiomers of molecule 3 and squares around the molecules that are diastereomers of molecule 3. NH2 H₂N H₂N NH2 NH2 NH2 molecule 3

2. Draw the two chair conformations for both cis- and trans-2-isopropylcyclohexanol (a planar form is shown below without specifying cis or trans). For each isomer, circle the lower energy chair conformation and also indicate which isomer, the cis or the trans, is the more stable isomer. ОН

Draw a pair of cis/trans stereoisomers with a molecular formula of C7H14.  Label the cis compound and the trans compound