The cis-and trans-3-t-butylcyclobutanols have been prepared and equilibrated with aluminum isopropoxide in isopropyl alcohol at different temperatures. The thermodynamic parameters (trans to cis) are AH=-1.6 kcal/mol, AS=-1.1 cal/(deg mol), and AGloo=-1.15 kcal/mol. The equilibration of ethyl 3-t-butylcyclobutanecarboxylate with sodium ethoxide in ethanol at different temperatures gives AH=-0.8 kcal/mol, AS=-0.7 cal/(deg mol), and ...