The dependence of the solid state structures of bisparaphenylene-(3n+ 4)-crown-n ethers upon macrocyclic ring size

Abstract
X-Ray crystallography on the free BPP(3n+4)Cn ethers where n= 7,8,10,11, and 12 reveals a conformational dependence for the macrocycles which is reflected in their cavity sizes, with a maximum for n= 10, and in the relative orientations of the two hydroquinol rings, almost orthogonal for n= 7 and parallel or nearly parallel for n= 8,10,11, and 12, with respect to each other.