Integrating Metal-Catalyzed C–H and C–O Functionalization To Achieve Sterically Controlled Regioselectivity in Arene Acylation
作者:Nicholas A. Serratore、Constance B. Anderson、Grant B. Frost、Truong-Giang Hoang、Steven J. Underwood、Philipp M. Gemmel、Melissa A. Hardy、Christopher J. Douglas
DOI:10.1021/jacs.8b06476
日期:2018.8.8
organometallic chemists is the direct functionalization of the bonds most recurrent in organic molecules: C-H, C-C, C-O, and C-N. An even grander challenge is C-C bond formation when both precursors are of this category. Parallel to this is the synthetic goal of achieving reaction selectivity that contrasts with conventional methods. Electrophilic aromatic substitution (EAS) via Friedel-Crafts acylation
有机金属化学家的一个主要目标是将有机分子中最常见的键直接官能化:CH、CC、CO 和 CN。当两种前体都属于此类时,更大的挑战是 CC 键的形成。与此并行的是实现与传统方法形成对比的反应选择性的合成目标。通过 Friedel-Crafts 酰化的亲电芳香取代 (EAS) 是合成芳基酮的最著名方法,芳基酮是许多药物、农用化学品、香料、染料和其他商品化学品的常见结构基序。然而,只有当所需的酰化位点与反应的电子控制区域选择性一致时,EAS 合成策略才有效。在此,我们报告了空间控制的区域选择性芳烃酰化与水杨酸酯通过铱催化获得明显取代的二苯甲酮。实验和计算数据表明,一种独特的反应机制将 CO 活化和 CH 活化与单一铱催化剂相结合,无需外源氧化剂或碱。我们公开了对芳烃和酯成分的合成范围的广泛探索,最终以简明的合成强效抗癌剂羟基苯司他汀。
Copper-catalyzed ortho-acylation of phenols with aryl aldehydes and its application in one-step preparation of xanthones
作者:Jun Hu、Enoch A. Adogla、Yong Ju、Daping Fan、Qian Wang
DOI:10.1039/c2cc36176k
日期:——
In the presence of triphenylphosphine, copper(II) chloride can catalyze an intermolecular ortho-acylation reaction of phenols with aryl aldehydes. The reaction proceeds smoothly with a wide range of starting materials, and furthermore, it can be used to synthesize xanthone derivatives in a single step in high yields.
Chiral Phosphoric Acid Catalyzed Enantioselective Transfer Hydrogenation of ortho-Hydroxybenzophenone NH Ketimines and Applications
作者:Thanh Binh Nguyen、Qian Wang、Françoise Guéritte
DOI:10.1002/chem.201101694
日期:2011.8.22
Unprotected synthesis: The first enantioselective chiral phosphoric acid catalyzed transferhydrogenation of unprotected ortho‐hydroxybenzophenone NH imines by using a Hantzsch ester as the hydrogen source afforded the corresponding chiral N,O‐unprotected ortho‐hydroxydiarylmethylamines in high yields with excellent enantioselectivities (see scheme).
The first enantioselective chiral phosphoricacid-catalyzedtransferhydrogenation of N-aryl-ortho-hydroxybenzophenoneketimines using a Hantzsch ester as hydrogen source was developed to afford, after removal of the N-aryl group, the corresponding chiral diarylmethylamines in high yields and enantioselectivities.
Aerobic Copper‐Catalyzed Salicylaldehydic C
<sub>formyl</sub>
−H Arylations with Arylboronic Acids
作者:Lin Xiao、Tao‐Tao Lang、Ying Jiang、Zhong‐Lin Zang、Cheng‐He Zhou、Gui‐Xin Cai
DOI:10.1002/chem.202004810
日期:2021.2.15
We report a challenging copper‐catalyzed Cformyl−H arylation of salicylaldehydes with arylboronic acids that involves unique salicylaldehydic copper species that differ from reported salicylaldehydic rhodacycles and palladacycles. This protocol has high chemoselectivity for the Cformyl−H bond compared to the phenolic O−H bond involving copper catalysis under high reaction temperatures. This approach
我们报道了具有挑战性的水杨醛与芳基硼酸的铜催化的C甲酰基-H芳基化反应,其中涉及独特的水杨醛醛铜种类,不同于报道的水杨醛Rhodacycles和palladacycles。与在高反应温度下涉及铜催化的酚式O-H键相比,该方案对C甲酰基-H键具有较高的化学选择性。该方法与广泛的水杨醛和芳基硼酸底物兼容,包括雌酮和咔唑衍生物,可产生相应的芳基化产物。机理研究表明,水杨醛底物的2-羟基基团通过Cu I / Cu II触发水杨醛醛铜络合物的形成/ Cu III催化循环。