Unusual structure of a biphenyl fragment: the important role of weak interactions

Abstract

1,5-Bis([1,1′-biphenyl]-4-yl)-5-hydroxy-3-methylheptane-1,6-dione, C32H30O3, was investigated by X-ray analysis, quantum chemical calculations and AIM (atoms in molecules) analysis. It was shown that four intramolecular C—H...π forces are established between the two biphenyl fragments. C—H...π interactions lead to a bending of the biphenyl part. The energy of the intramolecular interactions was estimated and the exclusive role of the moment of force was established.