Water-Sculpting of a Heterogeneous Nanoparticle Precatalyst for Mizoroki–Heck Couplings under Aqueous Micellar Catalysis Conditions
作者:Haobo Pang、Yuting Hu、Julie Yu、Fabrice Gallou、Bruce H. Lipshutz
DOI:10.1021/jacs.0c11484
日期:2021.3.10
Powdery, spherical nanoparticles (NPs) containing ppm levels of palladium ligated by t-Bu3P, derived from FeCl3, upon simple exposure to water undergo a remarkable alteration in their morphology leading to nanorods that catalyzeMizoroki–Heck (MH) couplings. Such NP alteration is general, shown to occur with three unrelated phosphine ligand-containing NPs. Each catalyst has been studied using X-ray
粉末状球形纳米粒子 (NPs) 含有 ppm 级的钯,由来自 FeCl 3的t- Bu 3 P连接,在简单暴露于水中后,其形态发生显着变化,导致纳米棒催化 Mizoroki-Heck (MH) 偶联。这种 NP 改变是普遍的,显示发生在三个不相关的含膦配体的 NP 中。已使用 X 射线光电子能谱 (XPS)、能量色散 X 射线能谱 (EDX)、透射电子显微镜 (TEM) 和低温透射电子显微镜 (cryo-TEM) 分析研究了每种催化剂。专门依赖于含有t- Bu 3 的NPs 的联轴器P-连接的 Pd 在室温至 45 °C 之间的水性胶束催化条件下发生,并显示出广泛的底物范围。与这项新技术相关的其他关键特性包括产品中残留的 Pd 低、水性反应介质的循环利用以及相关的低 E 因子。galipinine 是汉考克生物碱家族的一员,其前体的合成暗示了潜在的工业应用。
Catalytic Asymmetric Hydrophosphinylation of 2‐Vinylazaarenes to Access P‐Chiral 2‐Azaaryl‐Ethylphosphine Oxides
A chiral Brønsted acid-catalysed asymmetrichydrophosphinylation of 2-vinylazaarenes is developed. The method provides a modular and efficient access to P-chiral 2-azaaryl-ethylphosphine oxides while also realizing the precise kinetic resolution of secondary phosphine oxides. Given the verified promise of the chiralphosphines as the chiral ligands, this work considerably enriches the toolkit of asymmetric
The development of catalytic asymmetric radical reactions is an attractive but formidable task. The high reactivity of radicals enables the use of readily accessible feedstocks and mild reaction conditions, but it leads to substantial difficulty for chiral catalysts to provide sufficient enantiocontrol. Moreover, a racemic background process is often inevitable, further deteriorating enantioselectivity
nickel-catalyzed acylation of vinylpyridines with CO at atmospheric pressure is reported, allowing for an expedient approach to synthesize β-acyl pyridine derivatives with high regio- and chemoselectivity. The electron-withdrawing property of pyridine plays pivotal roles in activating the alkenyl group, thereby facilitating this carbonylative process. In addition to vinylpyridines, other alkenylheterocycles
报道了在大气压下镍催化乙烯基吡啶与 CO 的酰化反应,为合成具有高区域选择性和化学选择性的 β-酰基吡啶衍生物提供了一种简便的方法。吡啶的吸电子特性在激活烯基方面发挥着关键作用,从而促进了这一羰基化过程。除乙烯基吡啶外,其他烯基杂环如噻唑和喹啉也适用于该方法。
LUMINESCENCE ENHANCER
申请人:FUJIREBIO INC.
公开号:EP2028250A1
公开(公告)日:2009-02-25
An object of the present invention is to provide a luminescence enhancer by which a luminescence such as chemiluminescence can be enhanced with higher sensitivity and the luminescence can be continued over a prolonged period of time. That is, the present invention provides a luminescence enhancer containing a heteropolymer as an active ingredient, a method for measuring the luminescence using a luminescent substrate and said luminescence enhancer, and a method for analyzing a substance to be measured in a specimen wherein the specimen, an antigen and/or antibody corresponding to a substance to be measured, an antigen and/or antibody labeled-form with an activator and a luminescent substrate are reacted in the presence of said luminescence enhancer to measure the luminescence.