2021年2月25日，美国加州大学圣芭芭拉分校Bruce H. Lipshutz课题组在《美国化学会杂志》发表论文，宣布他们研究出水塑性非均相纳米粒子预催化剂，用于在水胶束催化条件下的Mizoroki-Heck偶联。

课题组研究出粉状球形纳米颗粒(NPs)，含有ppm水平的钯，由t-Bu₃P连接，由FeCl₃衍生，简单暴露在水里，其形态会发生显著变化，导致纳米棒催化Mizoroki-Heck (MH)耦合反应。这种NP的改变是普遍的，表现在发生在三个不相关的含膦配体的NPs。

研究人员使用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）分析对每种催化剂进行了研究。在水性胶束催化条件下，室温至45°C之间发生的偶联特别依赖于含t-Bu₃P连接的Pd的NP，并显示出较宽的底物范围。

与这项新技术相关的其他关键特性包括产品中的低残留Pd、水相反应介质的循环利用以及相关的低E因子。半胱氨酸碱（汉考克生物碱家族的成员）的前体的合成显示了该技术潜在的工业应用。

附：英文原文

Title: Water-Sculpting of a Heterogeneous Nanoparticle Precatalyst for Mizoroki–Heck Couplings under Aqueous Micellar Catalysis Conditions

Author: Haobo Pang, Yuting Hu, Julie Yu, Fabrice Gallou, Bruce H. Lipshutz

Issue&Volume: February 25, 2021

Abstract: 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 catalyze Mizoroki–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 photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and cryogenic transmission electron microscopy (cryo-TEM) analyses. Couplings that rely specifically on NPs containing t-Bu3P-ligated Pd occur under aqueous micellar catalysis conditions between room temperature and 45 °C, and show broad substrate scope. Other key features associated with this new technology include low residual Pd in the product, recycling of the aqueous reaction medium, and an associated low E Factor. Synthesis of the precursor to galipinine, a member of the Hancock family of alkaloids, is suggestive of potential industrial applications.

DOI: 10.1021/jacs.0c11484

Source: https://pubs.acs.org/doi/10.1021/jacs.0c11484