Electrochemical oxidation of 2,4‐dimethylphenol directly provides pentacyclic systems being generated by an oxidative trimerization. The major pentacyclic scaffold is exclusively formed as a single diastereoisomer and is easily isolated. Three further pentacyclic compounds which occur in minor quantities were also fully characterized including their solid‐state structures. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Substituted phenols were anodically coupled to the corresponding 2,2'-biphenols via tetraphenoxy borate derivatives. This electrochemical method is particularly useful for methyl-substituted substrates, such as 2,4-dimethyl phenol. The selective ortho-coupling reaction can be easily performed on a multikilogram scale.

Anodic conversion of 2,4‐dimethylphenol on boron‐doped diamond (BDD) electrodes under solvent‐free conditions results in an unusual highly selective formation of the desired 2,2′‐biphenol, representing the best electrochemical synthesis for this particular compound. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Tetraphenoxyborates are reliably prepared in a two-step sequence, exploiting less corrosive reagents like boric acid and the corresponding phenols. The broad scope of this transformation is demonstrated in 22 examples. Several solid-state structures reveal the preferential conformation of the phenoxy moieties allowing cation interaction. Furthermore, a

The synthesis and biological evaluation of two ortho-carborane derivatives which contain a 5,6,7-trimethoxyindole (TMI) unit for use in boron neutron capture therapy is described. The TMI moiety is known to be the DNA-binding part of the highly potent anticancer agent duocarmycin A. The ortho-carborane derivatives were prepared from amino alkynes which were bound to a protected TMI carboxylic acid. Addition of decaborane(14) to the alkyne triple bond with subsequent removal of the tert-butoxycarbonyl (Boc) and benzyl protecting groups gave the desired product. Boron uptake from the ortho-carborane derivatives into B-16 melanoma cells was higher and faster than that observed with L-p-boronophenylalanine (BPA), which is in use in the clinic.