Die Strukturen der mittleren Ringverbidungen. XIII. Zwei neue Konformationen des Cyclodecanringes

The results of the X-ray analysis of 1,1,5,5-tetramethylcyclodecane-8-carboxylic acid do not correspond to a reasonable molecular structure. When used as a startingpoint for a strain-energy minimization calculation based on semi-empirical potential functions, they lead to two new conformations for the cyclodecane ring. It is shown that the X-ray results can be explained by assuming that the crystal consists of a random mixture of these two conformations.