Rhodium Porphyrins for Catalytic C-H Activation

描述（由申请人提供）：常见但不反应的C-H键向其他官能团的化学选择性转化具有革命性化学合成的潜力。本研究的主要目的是开发铑卟啉催化剂，以活化和功能化sp3杂化C-H键。铑（II）卟啉络合物可以化学计量地活化sp3 C-H键超过sp2 C-H键，而不需要在基底内引导基团，同时耐受生物活性化合物中存在的官能团的类型。本研究将试图使这一反应更广泛地应用，使化学计量的过程成为催化的一个，通过使用氮氧自由基，把这个C-H活化的产物，铑（III）烷基和氢化物物种，铑（II）卟啉和有用的有机产品，即烯烃。氮氧自由基被选择用于这项研究的基础上，这些化合物的已知能力，以转换一些铑（III）卟啉？铑（II）卟啉和氮氧促进转化铑（III）卟啉烷基到烯烃。本文提出的新的氮氧自由基将通过避免铑（II）卟啉与先前使用的氮氧自由基的已知副反应而允许催化。

DESCRIPTION (provided by applicant): The chemoselective transformation of common but unreactive C-H bonds to other functional groups has the potential to revolutionize chemical synthesis. The primary goal of the proposed research is to develop rhodium porphyrin catalysts to activate and functionalize sp3 hybridized C-H bonds. Rhodium (II) porphyrin complexes can stoichiometrically activate sp3 C-H bonds over sp2 C-H bonds without the need for directing groups within the substrate while tolerating the types of functional groups present in bioactive compounds. This research will attempt to make this reaction more widely applicable by making the stoichiometric process into catalytic one by using nitroxide radicals to turn the products of this C-H activation, rhodium (III) alkyl and hydride species, into rhodium (II) porphyrins and useful organic products, namely alkenes. Nitroxide radicals were chosen for this study based on the known ability of these compounds to covert some rhodium (III) porphyrin hydrides to rhodium (II) porphyrins and the nitroxide promoted conversion of rhodium (III) pophyrin alkyls into alkenes. The new nitroxide radicals proposed herein will allow catalysis by avoiding known side reactions of the rhodium (II) porphyrins with previously used nitroxide radicals.