Die Strukturen der mittleren Ringverbindungen. XII. Kristallstruktur der 1,1,5,5-Tetramethylcyclodecan-8-carbonsäure

Crystals of 1,1,5,5-tetramethylcyclodecane-8-carboxylic acid are monoclinic, a = 9.22 Å, b = 14.81 Å, c = 11.58 Å, β = 111° 0′, space group P2₁/c with 4 molecules in the unit cell. The structure has been solved by direct methods and refined by full-matrix least-squares analysis of three-dimensional intensitiy data. The conformation of the ring differs from the previously observed cyclodecane conformation, but the detailed results are abnormal in a number of ways (extremely short C? C bond lengths, wide C? C? C bond angles, large temperature factors). The possibility is discussed that the crystal structure is disordered.