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. !

项目摘要氧化底物功能化为引入新的化学功能和结构复杂性。合成电催化为可持续氧化物提供了一个概念平台通过避免对化学计量化学氧化的需求，以及所隐含的浪费的技术这些试剂。实际上，许多有机分子的慢速界面电子转移化学可防止电化学方法的宽度应用于精细化学合成。此外，单电子转移流程是电化学策略的货币，不是常见的基本步骤合成重要的转换。该提议的核心假设是高价值碘电催化将提供一个平台，以实现宽阔的氧化底物功能化电化学。该假设是关于高价值碘化学的预测众所周知的试剂是参与选择性的两电子氧合，胺化，卤素化，和氢化碳酸氢转移反应。成功发展高价值碘电催化将实质上影响了精细化学物质的合成，例如分子疗法。该建议旨在首先通过电化学生成的碘过度进行电催化物种。具体而言，拟议的策略利用了先前未批准的策略来综合高价值碘物种 - 单电子途径可有效访问选择性两电子基于高价值碘化合物的化学氧化剂 - 开发合成过度碘电催化。初步数据，表明电化学生成的羧基自由基使便利高价值碘物种的电合合成和电化学产生的碘过度物种是氧化C – H/N – H偶联的合格介体。我们建议将这些初步结果扩展到发展新的合成有用的转换，例如氧化C – H功能化。此外，对芳基碘化物氧化涉及的基本步骤的基本理解提供了开发新型碘合成方法所需的化学见解扩展过度碘催化的底物氧化的合成范围。这些的长期目标努力是确定新的催化剂脚手架以启用催化剂控制的位点和立体选择性C – H 功能化将直接访问复杂的分子体系结构功能化代谢后果的位置，这将影响对药物代谢产物的评估并影响发现新的治疗剂。拟议的研究工作将共同提供新的可持续性合成方法并扩展可用于合成的转换的合成工具箱功能分子。呢

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.