New liquid triarylamine-siloxane hybrid materials are produced using the Piers-Rubinsztajn reaction. Under mild conditions, liquid analogues of conventional and commonly crystalline triarylamines are easily synthesized from readily available or accessible intermediates. Using a diverse selection of triarylamines, we explored the effects of siloxane group and substitution pattern on the physical properties of these materials, and we have demonstrated that relatively large molecular liquids with desirable electrochemical properties can be produced. The interactions between the strongly Lewis acidic catalyst used for this transformation, tris(pentafluorophenyl)borane (BCF), and the Lewis basic triarylamine substrates were studied. Through UV-vis-NIR and (19)F NMR spectroscopy, we have proposed that the catalyst undergoes a reversible redox reaction with the substrates to produce a charge transfer complex. The formation of this charge transfer complex is sensitive to the oxidation potential of the triarylamine and can greatly affect the kinetics of the Piers-Rubinsztajn reaction.

A case of spinal subarachnoid haemorrhage secondary to degenerative changes in a cervical schwannoma is presented. The problems associated with diagnosis as well as the possible mechanisms resulting in haemorrhage from spinal tumours are reviewed.

A case of basilar invagination which is thought to have arisen from the patient's intrauterine exposure to phenytoin is presented. The patient was treated surgically by foramen magnum decompression and occipito-cervical fusion, and by transoral resection of the clivus. His symptoms of brain stem compression were alleviated and the role of phenytoin in the production of his craniocervical abnormality is discussed.