Iron catalyzed cross coupling reactions of aromatic compounds
申请人:——
公开号:US20030220498A1
公开(公告)日:2003-11-27
A process for the production of compounds Ar—R
1
by means of a cross-coupling reaction of an organometallic reagent R
1
—M with an aromatic or heteroaromatic substrate Ar—X catalyzed by one or several iron salts or iron complexes as catalysts or pre-catalysts, present homogeneously or heterogeneously in the reaction mixture. This new invention exhibits substantial advantages over established cross coupling methodology using palladium- or nickel complexes as the catalysts. Most notable aspects are the fact that (i) expensive and/or toxic nobel metal catalysts are replaced by cheap, stable, commercially available and toxicologically benign iron salts or iron complexes as the catalysts or pre-catalysts, (ii) commercially attractive aryl chlorides as well as various aryl sulfonates can be used as starting materials, (iii) the reaction can be performed under “ligand-free” conditons, and (iv) the reaction times are usually very short.
and -CF(3) groups are compatible. The method also allows for consecutive cross-coupling processes in one pot, as exemplified by the efficient preparation of compound 12, and has been applied to the first synthesis of the cytotoxic marine natural product montipyridine 8. In contrast to the clean reaction of (hetero)aryl chlorides, the corresponding bromides and iodides are prone to a reduction of their
The invention provides novel inhibitors of hedgehog signaling that are useful as a therapeutic agents for treating malignancies where the compounds have the general formula I:
wherein A, X, Y R
1
, R
2
, R
3
, R
4
, m and n are as described herein.
General Chemoselective Suzuki–Miyaura Coupling of Polyhalogenated Aryl Triflates Enabled by an Alkyl-Heteroaryl-Based Phosphine Ligand
作者:Chau Ming So、On Ying Yuen、Shan Shan Ng、Zicong Chen
DOI:10.1021/acscatal.1c02146
日期:2021.7.2
describes a general chemoselective Suzuki–Miyauracoupling of polyhalogenated aryl triflates with the reactivity order of C–Cl > C–OTf using a Pd/L33 catalyst. The methine hydrogen and the steric hindrance offered by the alkyl bottom ring of L33 were found to be key factors in reactivity and chemoselectivity. With the Pd/L33 catalyst, a wide range of polyhalogenated (hetero)aryl triflates, which were independent