Ziegler's2 tetraphenylallyl radical,(C6&) zC= CH-c (C6H5) 2, and its substituted derivatives are particularly remarkable in that although they contain only two aryl groups on the methane carbon atom, molecular weight determinations show them to be largely monomolecular. Their deep colors in solution or in the solid state, and their sensitivity toward oxygen also attest their high degree of dissociation. This degree of dissociation, so much ...
![9-chloro-9-[fluoren-9-ylidene(phenyl)methyl]fluorene Structure](https://image.chemsrc.com/caspic/426/72087-83-3.png)