Part I: Mechanistic insight into the photooxidation of enecarbamates. Part II: Catalytic functionalization of terminal unactivated carbon-hydrogen bonds. Part III: Design of smart materials; synthesis of cross polymerisable photoprotected functional macromonomers.

摘要

Part I. Oxazolidinone-substituted, chiral enecarbamates are versatile substrates for the study of conformational, electronic, stereoelectronic, and steric effects on the stereoselectivity of the oxidation at the alkene functionality. It was previously reported that the photooxygenation of the Z isomers of the enecarbamates leads to diastereomerically pure dioxetanes, which result from the attack of singlet oxygen exclusively on the face anti to the isopropyl substituent of the oxazolidinone stereogenic center at the C-4 position. To gain mechanistic insight into the factors that control the oxidative reactivity of these chiral substrates and the selectivity of the oxidant, we have examined the influence of small structural changes in the enecarbamates, as well as the nature of the oxidizing species. The results are analyzed in terms of a mechanistic model to account for the unusual reactivity and selectivity effects that have been observed on varying the temperature and solvent.; Part II. Unactivated C-H bonds (alkanes segments) are believed to be particularly unreactive materials. Based on previous reports of metal mediated activation of unactivated C-H bonds through internal coordination by a functional group, we envisioned new catalytic reactions incorporating such a step. The present work describes our efforts towards such a goal and the development of catalytic hydroxylation reaction. Analysis of the results will gear towards the scope and limitations of the system.; Part III. Developments of material able to alter their physical properties when subjected to a specific stimuli, is an important part of material science. Light induced changes in structures are highly desirable systems. We report the synthesis of well defined cross polymerizable macromonomers based on photoprotected functional monomers using living free radical polymerization techniques, namely Atom Transfer Radical Polymerization.