Metal-Free Electrocatalysis for Fine-Chemical Synthesis

用于精细化学合成的无金属电催化

基本信息

批准号：
10667442
负责人：
David C Powers
金额：
$ 36.33万
依托单位：
TEXAS A&M UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2025-07-31
项目状态：
未结题

项目摘要

Project Summary Oxidative substrate functionalization provides the opportunity to introduce new chemical functionality and structural complexity. Synthetic electrocatalysis provides a conceptual platform for sustainable oxidation technologies by obviating the need for stoichiometric chemical oxidants, and the attendant waste implied by these reagents. In practice, slow interfacial electron transfer chemistry of many organic molecules prevents widespread application of electrochemical methods to fine-chemical synthesis. Further, single electron-transfer processes, which are the currency of electrochemical strategies, are not common elementary steps in synthetically important transformations. The central hypothesis of this proposal is that development of hypervalent iodine electrocatalysis will provide a platform to achieve a broad array of oxidative substrate functionalization electrochemically. This hypothesis is predicated on the rich chemistry of hypervalent iodine reagents, which are well-known to participate in selective two-electron oxygenation, amination, halogenation, and hydrocarbyl transfer reactions. Successful development of hypervalent iodine electrocatalysis would substantially impact the synthesis of fine chemicals, such as molecular therapeutics. This proposal aims to first develop electrocatalysis via electrochemically generated hypervalent iodine species. Specifically, the proposed strategy leverages a previously unappreciated strategy for the synthesis of hypervalent iodine species – that one-electron pathways provide efficient access to selective two-electron chemical oxidants based on hypervalent iodine compounds – to develop synthetic hypervalent iodine electrocatalysis. Preliminary data indicate that electrochemically generated carboxy radicals enable facile electrosynthesis of hypervalent iodine species and that electrochemically generated hypervalent iodine species are competent mediators of oxidative C–H / N–H coupling. We propose to extend these preliminary results to develop new synthetically useful transformations, such as oxidative C–H functionalization. Further, the fundamental understanding of the elementary steps involved in the oxidation of aryl iodides provides the chemical insight necessary to develop novel methods of hypervalent iodine synthesis that will substantially expand the synthetic scope of hypervalent iodine catalyzed substrate oxidation. A long-term goal of these efforts is to identify new catalyst scaffolds to enable catalyst-controlled site- and stereoselective C–H functionalization which would provide direct access to complex molecular architectures functionalized at positions of metabolic consequence, which would impact the evaluation of drug metabolites and impact the discovery of new therapeutics. Together, the proposed research efforts will provide both new sustainable synthetic methods and expand the synthetic toolbox of transformations that are available for the synthesis of functional molecules. !

项目概要氧化底物功能化提供了引入新化学功能和结构复杂性为可持续氧化提供了一个概念平台。通过消除对化学计量化学氧化剂的需要以及随之而来的浪费来实现技术在实践中，许多有机分子的缓慢界面电子转移化学会阻碍这些反应。电化学方法在精细化学合成中的广泛应用过程是电化学策略的通用过程，但并不是常见的基本步骤该提案的中心假设是发展。高价碘电催化将为实现广泛的氧化底物提供一个平台该假设基于高价碘丰富的化学性质。众所周知，这些试剂参与选择性双电子氧化、胺化、卤化、和烃基转移反应的成功发展将促进高价碘电催化反应的发展。显着影响精细化学品的合成，例如分子疗法。该提案旨在首先通过电化学产生的高价碘开发电催化具体来说，所提出的策略利用了以前未受重视的合成策略。高价碘物种——单电子途径提供了选择性双电子的有效途径基于高价碘化合物的化学氧化剂——开发合成高价碘初步数据表明电化学产生的羧基能够轻松实现。高价碘物质的电合成以及电化学产生的高价碘物质是氧化 C-H / N-H 偶联的有效介体，我们建议将这些初步结果扩展到。开发新的合成有用的转化，例如氧化C-H官能化。对芳基碘化物氧化所涉及的基本步骤的基本理解提供了开发高价碘合成新方法所必需的化学洞察力，该方法将显着扩大高价碘催化底物氧化的合成范围是这些的长期目标。旨在确定新的催化剂支架，以实现催化剂控制的位点和立体选择性 C–H 功能化，这将提供直接访问功能化的复杂分子结构代谢后果的位置，这将影响药物代谢物的评估并影响总之，拟议的研究工作将提供新的可持续疗法。合成方法并扩展可用于合成的转化合成工具箱功能分子。！

项目成果

期刊论文数量（7）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Diversification of Amidyl Radical Intermediates Derived from C-H Aminopyridylation.

DOI：
10.1021/acs.orglett.2c00869
发表时间：
2022-04-15
期刊：
ORGANIC LETTERS
影响因子：
5.2
作者：
Maity, Asim;Roychowdhury, Pritam;Herrera, Roberto G.;Powers, David C.
通讯作者：
Powers, David C.

Traceless Benzylic C-H Amination via Bifunctional N-Aminopyridinium Intermediates.

DOI：
10.1002/anie.202200665
发表时间：
2022-07-11
期刊：
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
影响因子：
16.6
作者：
Roychowdhury, Pritam;Herrera, Roberto G.;Tan, Hao;Powers, David C.
通讯作者：
Powers, David C.

Selective multi-electron aggregation at a hypervalent iodine center by sequential disproportionation.

通过顺序歧化在高价碘中心选择性多电子聚集。

DOI：
10.1039/d3cc00549f
发表时间：
2023
期刊：
Chemical communications (Cambridge, England)
影响因子：
0
作者：
Thai,Phong;Frey,BrandonL;Figgins,MatthewT;Thompson,RichardR;Carmieli,Raanan;Powers,DavidC
通讯作者：
Powers,DavidC

Iodine-Iodine Cooperation Enables Metal-Free C-N Bond-Forming Electrocatalysis via Isolable Iodanyl Radicals.

DOI：
10.1021/jacs.2c05562
发表时间：
2022-08-03
期刊：
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
影响因子：
15
作者：
Frey, Brandon L.;Figgins, Matthew T.;Van Trieste, Gerard P., III;Carmieli, Raanan;Powers, David C.
通讯作者：
Powers, David C.

N-Aminopyridinium reagents as traceless activating groups in the synthesis of N-Aryl aziridines.