NOVEL METHODS FOR PREPARATION OF SUBSTITUTED PYRIDINES AND RELATED NOVEL COMPOUNDS
申请人:Watkins Edmond Blake
公开号:US20200095245A1
公开(公告)日:2020-03-26
The present invention relates to novel methods of preparation of substituted pyridines and the compounds produced therefrom. In particular, the present invention provides efficient methods for the construction of diversely substituted pyridines, with varying substitution patterns under simple and metal-free conditions with high atom- and pot-economy and excellent functional group tolerance, and which are useful for the synthesis of natural products.
Visible‐light‐induced heterogeneous photocatalysis for decarboxylative alkynylation has been performed. The using of cheap, metal‐free and recyclable graphitic carbonnitride (g‐C3N4) as the photoredox catalyst in the process enables the facile transformation of a variety of carboxylic acids into structurally diverse alkyne‐containing molecular architectures under mild and environmentally‐benign conditions
可见光诱导的非均相光催化脱羧炔基反应。使用便宜,无金属且可回收的石墨氮化碳(g ‐ C 3 N 4)作为该过程中的光氧化还原催化剂,可以在温和和环境友好的条件下将多种羧酸轻松转化为结构多样的含炔分子结构。明显地,反应系统的非均质性质允许催化剂在多次运行中的回收和再利用而不损失反应性。光催化反应也可以以连续流动的方式进行并按比例放大至克级。此外,该策略在未活化烯烃的1,2氨基炔基化中的应用进一步凸显了该策略的制备能力。
Highly Efficient Copper-Catalyzed Synthesis of Internal Alkynes<i>via</i>Aerobic Oxidative Arylation of Terminal Alkynes
作者:Honghua Rao、Hua Fu、Yuyang Jiang、Yufen Zhao
DOI:10.1002/adsc.200900723
日期:2010.2.15
We have developed a novel and highlyefficient, copper-catalyzed synthesis of internal alkynes via oxidative couplings of aromatic boronic acids with terminalalkynes at room temperature. The protocol uses inexpensive copper(I) oxide [Cu2O] as the catalyst, oxygen in the air as the stoichiometric oxidant; no ligand and sealed reaction vessels are required, and remarkable functional group tolerability
Allylation of Carbon Pronucleophiles with Alkynes in the Presence of Palladium/Acetic Acid Catalyst
作者:Nitin T. Patil、Isao Kadota、Akinori Shibuya、Young Soo Gyoung、Yoshinori Yamamoto
DOI:10.1002/adsc.200404046
日期:2004.6
efficient and eco-chemical process for the allylation of carbon pronucleophiles with alkynes. The reaction of alkynes with various active methynes and methylenes in the presence of Pd(PPh3)4/acetic acid gave the corresponding allylated products in high yields and high regioselectivities. In the present catalytic system, the key is the use of carboxylic acid which dramatically enhances the rate of the
compounds have been studied. This investigation has led to the development of a mild, economic, and effective method for the synthesis of functionalized 4H-1,3-oxazines, 4H-1,3-thiazines, 4,5-dihydrothiazoles, and α-substituted enones. The structure of the propargylicsubstrate and the nature of electrophile influence both the outcome and regioselectivity of processes.