New Methods for Green Organic Synthesis

我们的建议侧重于开发铁和铋衍生的路易斯酸作为绿色催化剂。它们在合成化学中的应用需要进一步发展，因为与其他金属相比，它们对环境无害，相对无毒且经济。我们的研究目标是开发新的合成方法，重点是催化和对映选择程序，以直接制备药物感兴趣的分子。在现代有机合成中，催化不对称过程对于生产对映异构富集化合物是必不可少的，与需要化学计量量的手性试剂的方法相比，它提供了更经济、更环保的过程。我们的研究结果将为制备具有生物学意义的分子提供新的工具。这些研究将有助于开发新的绿色合成方法，使用环境友好和更经济的刘易斯酸催化剂。

Our proposal focuses on the development of iron and bismuth-derived Lewis acids as green catalysts. Their use in synthetic chemistry needs to be further developed because they are environmentally benign, relatively nontoxic and economic in comparison to other metals. The objective of our research is the development of new synthetic methods, with emphasis on catalytic and enantioselective procedures for the straightforward preparation of molecules of pharmaceutical interest. Catalytic asymmetric processes are indispensable for producing enantiomerically enriched compounds in modern organic synthesis, providing more economical and environmentally benign processes than methods requiring stoichiometric amounts of chiral reagents. Our results will lead to new tools for the preparation of molecules of biological interest. These studies will contribute to the development of new green synthetic methods using environmentally friendly and more economical Lewis acid catalysts. A first part of our proposal deals with the development of new chiral iron complexes for the enantioselective insertion reaction of diazo compounds into the SiH bond of silanes and the CH bond. Firstly, an enantioselective insertion reaction will be developed using Fe salts with C2-symmetric chiral ligands. Consequently, the enantioselective insertion reaction of Fe carbenoid vinyl intermediates into the SiH bond will be studied. The enantioselective synthesis of chiral allyl silanes is indeed of prime importance. The subsequent allylation reaction of carbonyl compounds using the synthesized enantio-enriched allyl silanes will be undertaken. Secondly, silanes will be used in the enantioselective hydrosilylation reaction of ketones catalyzed by iron salts and the above-selected chiral ligands. Various silanes will be employed in combination with a wide selection of Fe salts and chiral ligands. New chiral iron N-heterocyclic carbene (NHC) catalysts will be prepared and evaluated. A second part of our proposal will focus towards the development of an efficient catalytic system for the epoxidation and dihydroxylation of alkenes. A bioinspired non-heme iron complex capable of efficient oxidation of alkenes will be developed. Initial evidence showed that the previously prepared FeIIBolm's ligand complexes would have the appropriate geometry and electronics to work as oxidation catalysts. The asymmetric oxidation of sulfides using various iron chiral complexes will be studied as well. A third part of our research program will be devoted to the use of Bi-derived Lewis acids. These Bi complexes will be first used as catalysts for the enantioselective crotylation reaction. BiIII-derived heterobimetallic complexes will be prepared and used as catalysts for selected enantioselective reactions.