Conformation,in solution,of c-4-t-butyl-1-phenyl-r-1-(N-piperidyl)cyclohexane hydrochloride. The conformational energy of t-butyl

Although the hydrochloride of $\text{c}$-4-$\text{t}$-butyl-1-phenyl-$\text{c}$-1-(N-piperidyl)cyclohexane crystallizes in the conformation with axial $\text{t}$-butyl, it exists as an almost equimolar mixture of the two chair conformers in CD₂ Cl₂ solution. The position of equilibrium allows one to calculate ΔG°_{$\text{t}$-Bu} as ?4.9 kcal/mol.