Palladate Precatalysts for the Formation of C–N and C–C Bonds
摘要:
A series of imidazolium-based palladate precatalysts has been synthesized and the catalytic activity of these air- and moisture-stable complexes evaluated as a function of the nature of the imidazolium counterion. These precatalysts can be converted under catalytic conditions to Pd-NHC species capable of enabling the Buchwald-Hartwig aryl amination and the alpha-arylation of ketones. Both reactions can be carried out efficiently under very mild operating conditions. The effectiveness of the protocol was tested on functionality-laden substrates.
Atropisomerism in Diarylamines: Structural Requirements and Mechanisms of Conformational Interconversion
作者:Romain Costil、Alistair J. Sterling、Fernanda Duarte、Jonathan Clayden
DOI:10.1002/anie.202007595
日期:2020.10.12
exhibit atropisomerism (chirality due to restricted rotation). Previous examples have principally been tertiary amines, especially those with cyclic scaffolds. Little is known of the structural requirement for atropisomerism in structurally simpler secondary and acyclic diarylamines. In this paper we describe a systematic study of a series of acyclic secondary diarylamines, and we quantify the degree
DETECTION OF ANALYTES INCLUDING NITRO-CONTAINING ANALYTES
申请人:Swager Timothy M.
公开号:US20130065318A1
公开(公告)日:2013-03-14
Sensors and methods for determination of analytes are provided. Analytes including explosives (e.g., RDX or PETN) may be determined by monitoring, for example, a change in an optical signal of a material upon exposure to the analyte. In some embodiments, the analyte and the material may interact via a chemical reaction to form a new emissive species. Embodiments described herein may provide inexpensive sensors with high selectivity and sensitivity.
Mechanistic Insight into Cu-Catalyzed C–N Coupling of Hindered Aryl Iodides and Anilines Using a Pyrrol-ol Ligand Enables Development of Mild and Homogeneous Reaction Conditions
作者:Antoine de Gombert、Andrea Darù、Tonia S. Ahmed、Michael C. Haibach、Rei Li-Matsuura、Cassie Yang、Rodger F. Henry、Silas P. Cook、Shashank Shekhar、Donna G. Blackmond
DOI:10.1021/acscatal.2c06201
日期:2023.3.3
Mechanistic studies of the Cu-catalyzed C–N coupling of sterically hindered aryl iodides with sterically hindered anilines are carried out to shed light on how a recently reported pyrrol-ol ligand affects the reaction. Kinetic, spectroscopic, and computational tools help to probe the nature of the active catalyst species and the rate-determining step in the cycle. In contrast to most known Cu systems,
对空间位阻芳基碘化物与空间位阻苯胺的 Cu 催化 C-N 偶联进行了机理研究,以阐明最近报道的吡咯醇配体如何影响反应。动力学、光谱和计算工具有助于探索活性催化剂种类的性质和循环中的决速步骤。与大多数已知的铜系统相反,发现氧化加成先于胺的配位。这些研究有助于使用完全均匀的系统以及通过温度扫描和受控碱添加实现高产率的方案,在温和条件下设计高效工艺。对 XX 型配体获得的见解可能会导致在 Cu 催化偶联反应中挑战底物类别的通用方法。
Palladate Precatalysts for the Formation of C–N and C–C Bonds
作者:Caroline M. Zinser、Katie G. Warren、Fady Nahra、Abdullah Al-Majid、Assem Barakat、Mohammad Shahidul Islam、Steven P. Nolan、Catherine S. J. Cazin
DOI:10.1021/acs.organomet.9b00326
日期:2019.7.22
A series of imidazolium-based palladate precatalysts has been synthesized and the catalytic activity of these air- and moisture-stable complexes evaluated as a function of the nature of the imidazolium counterion. These precatalysts can be converted under catalytic conditions to Pd-NHC species capable of enabling the Buchwald-Hartwig aryl amination and the alpha-arylation of ketones. Both reactions can be carried out efficiently under very mild operating conditions. The effectiveness of the protocol was tested on functionality-laden substrates.