Question

Draw the two chair conformations of each compound and label the substituents as axial and equatorial. In each case, determine which conformation is more stable. a. trans-1-ethyl-2-isopropylcyclohexane b. trans-1-ethyl-3-methylcyclohexane C. Cis-1-ethyl-4-methylcyclohexane d. cis-1-ethyl-3-methylcyclohexane

Answer 1

o trans -l-ethyl-3-methyl cyclohexane Cha U Here ethyl group is above the plane & methyl group is below the plane, so whenever you are drawing the chair Information, make sure they are in same cant manner." - sh 1 11C13 you can choose any comor of chair to number!!! acial h وک 4 axial H- کا وار CH3 H I flippling equitorial 4 axial. Cha more stable bulky group ( calls) is at equitorial position, that make it mor stable less stable ~ here bulky group (Cars) is at axial position, make it less stable € Cis-t-ethyl-4-methyl cyclohexane. orial CQHS axial equitorial 0913/ " less stable bulky group at axial position, it feels greater equitorial more stable. fulty group Calls at equitosial repulsion from corial Hydrogens.

di cis-l-ethyl-3-methyl cyclohexane on CaHS equitorial Qxal - H GHS Н less stuble equitonalni more stable both the groups are at axial position more interaction from anal Ho making it less stable 60th the groups are at equitorid position $0 more stable than Other Conformation

③ trans-i-ethyl-2-isopropyl cyclohexane ch3 ₂ axial T H flipping equitorial 1 Cats axial C ~ CH3 less stable equitorial - this conformation is less more stable, stable because here both the substitutents are at arial bosition. Here, these substituents this conformation is feel repulsion from axial more stable because all the hich makes substitutents are at equitorial su position. Hydrogen, which makes this conformation less stable.