NiXantphos: a deprotonatable ligand for room-temperature palladium-catalyzed cross-couplings of aryl chlorides.
NiXantphos: a deprotonatable ligand for room-temperature palladium-catalyzed cross-couplings of aryl chlorides.
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DOI：
10.1021/ja411855d
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发表时间：
2014-04-30
影响因子：
15
通讯作者：
Walsh PJ
中科院分区：
文献类型：
--
作者：
Zhang J;Bellomo A;Trongsiriwat N;Jia T;Carroll PJ;Dreher SD;Tudge MT;Yin H;Robinson JR;Schelter EJ;Walsh PJ
尽管在过去的15年里见证了用于钯催化与芳基氯的交叉偶联的空间大体积和富含电子的烷基膦配体的发展，但基于三芳基膦或双齿膦配体的钯催化剂用于与未活化的芳基氯进行高效的室温交叉偶联反应的例子很少。在这里，我们报道了一种基于NiXantphos的钯催化剂，NiXantphos是一种可去质子化的螯合芳基二膦配体，用于在室温下氧化加成未活化的芳基氯。令人惊讶的是，大量配体的比较显示，在碱性反应条件下，得到的异双金属Pd-NiXantphos催化体系在与芳基氯化物的去质子化交叉偶联过程(DCCP)中表现出优于所有其他单齿和双齿配体。含有芳基氯化物的DCCP提供了多种三芳基甲烷产品，这是一类具有多种用途和有趣的生物活性的化合物。此外，在含有杂芳基和敏感官能团的芳氯底物存在下，DCCP表现出显著的化学选择性，这些官能团经过1，2-加成、羟醛反应、O-、N-、烯-α-和C(Sp2)-H芳基化。本文概述的Pd-NiXantphos催化剂体系的优点和重要性使其在Pd催化的芳基化反应中具有重要的应用价值。
Although the past 15 years have witnessed the development of sterically bulky and electron-rich alkylphosphine ligands for palladium-catalyzed cross-couplings with aryl chlorides, examples of palladium catalysts based on either triarylphosphine or bidentate phosphine ligands for efficient room temperature cross-coupling reactions with unactivated aryl chlorides are rare. Herein we report a palladium catalyst based on NiXantphos, a deprotonatable chelating aryldiphosphine ligand, to oxidatively add unactivated aryl chlorides at room temperature. Surprisingly, comparison of an extensive array of ligands revealed that under the basic reaction conditions the resultant heterobimetallic Pd–NiXantphos catalyst system outperformed all the other mono- and bidentate ligands in a deprotonative cross-coupling process (DCCP) with aryl chlorides. The DCCP with aryl chlorides affords a variety of triarylmethane products, a class of compounds with various applications and interesting biological activity. Additionally, the DCCP exhibits remarkable chemoselectivity in the presence of aryl chloride substrates bearing heteroaryl groups and sensitive functional groups that are known to undergo 1,2-addition, aldol reaction, and O-, N-, enolate-α-, and C(sp2)–H arylations. The advantages and importance of the Pd–NiXantphos catalyst system outlined herein make it a valuable contribution for applications in Pd-catalyzed arylation reactions with aryl chlorides.
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影响因子：
8.4
作者：
Bellomo, Ana;Zhang, Jiadi;Walsh, Patrick J.
通讯作者：
Walsh, Patrick J.
影响因子：
16.6
作者：
Bellomo, Ana;Celebi-Olcum, Nihan;Dreher, Spencer D.
通讯作者：
Dreher, Spencer D.
影响因子：
15
作者：
Barrios-Landeros F;Carrow BP;Hartwig JF
通讯作者：
Hartwig JF
影响因子：
15
作者：
Barder, TE;Walker, SD;Buchwald, SL
通讯作者：
Buchwald, SL
影响因子：
15
作者：
Amatore, C;Broeker, G;Khalil, F
通讯作者：
Khalil, F