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。
Armeniaspiroles, a new class of antibacterials: antibacterial activities and total synthesis of 5-chloro-Armeniaspirole A
Armeniaspiroles, a novel class of natural products isolated from Streptomyces armeniacus, are characterized by a novel spiro[4.4]non-8-ene scaffold. Various derivatives of Armeniaspiroles could be obtained by halogenation, alkylation, addition/elimination or reductions. A total synthesis of the 5-chloro analog of Armeniaspirole A has been accomplished in a linear six-step sequence. 5-Chloro-Armeniaspirole A exhibits good activity against a range of multidrug-resistant, Gram-positive bacterial pathogens. (C) 2012 Elsevier Ltd. All rights reserved.
Isolation and Structural Elucidation of Armeniaspirols A-C: Potent Antibiotics against Gram-Positive Pathogens
malt‐containing medium. The challenging structural elucidation of the isolated compounds was achieved by using three independent methods, that is, chemical degradation followed by NMR spectroscopy, a computer‐assisted structure prediction algorithm, and X‐ray crystallography. The compounds, named armeniaspirol A–C (2–4), exhibit a compact, hitherto unprecedented chlorinated spiro[4.4]non‐8‐ene scaffold. Labeling