A nordehydroabietyl amide-containing chiral diene for rhodium-catalysed asymmetric arylation to nitroolefins
作者:Ruikun Li、Zhongqing Wen、Na Wu
DOI:10.1039/c6ob02202b
日期:——
A highlyenantioselectiverhodium catalysed asymmetric arylation (RCAA) of nitroolefins with arylboronicacids is presented using a newly developed, C1-symmetric, non-covalent interacted, phellandrene derived, nordehydroabietyl amide-containing chiral diene under mild conditions. Stereoelectronic effects were studied, suggesting an activation of the bound substrate through the secondary amide as a
A fluoroustetraarylporphyrin has been prepared in a single reaction step starting from commercially available 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin [TPP(OH)4]. The new compound was successfully employed as a sensitizer in photooxygenationreactions carried out under homogeneous conditions, showing activity comparable to the standard 5,10,15,20-tetraphenylporphyrin (TPP) sensitizer. Photooxygenation
High-Throughput Synthesis of (<i>S</i>)-α-Phellandrene through Three-Step Sequential Continuous-Flow Reactions
作者:Samuel J. Miller、Haruro Ishitani、Yuichi Furiya、Shu̅ Kobayashi
DOI:10.1021/acs.oprd.0c00391
日期:2021.2.19
The combination of continuous-flow processing with heterogeneous catalysts allows for efficient, sustainable, multistep synthesis. Here, we report the continuous-flow synthesis of a valuable terpene product, phellandrene, from a readily available natural feedstock. The protocol consists of selective hydrogenation using a highly active and stable supported platinumcatalyst, dehydrative hydrazone formation
Carbonyl-η-hexamethylbenzene complexes of osmium. Carbon-hydrogen activation by (η-C6Me6)Os(CO)(H)2
作者:William A. Kiel、Richard G. Ball、William A.G. Graham
DOI:10.1016/0022-328x(90)85149-s
日期:1990.2
Reduction of (η-C6Me6)Os(CO)Cl2 (1) with zinc/acetic acid/methanol gives (η-C6Me6)Os(CO)(Cl)H (2), which can be further reduced with Na[H2Al(OCH2- CH2OCH3)2] to (η-C6Me6)Os(CO)H2 (3). Photolysis of 3 in hydrocarbons (benzene, cyclohexane, neopentane) results in formation of the carbon-hydrogen bond activation products (η-C6Me6Os(CO)(R)(H) (6a–6c, R = C6H5, C6H11 and CH2C(CH3)3, respectively) and free
用锌/乙酸/甲醇还原(η- C6 Me 6)Os(CO)Cl 2(1)得到(η- C6 Me 6)Os(CO)(Cl)H(2)进一步用Na [H 2 Al(OCH 2 -CH 2 OCH 3)2 ]还原为(η- C6 Me 6)Os(CO)H 2(3)。3在碳氢化合物(苯,环己烷,新戊烷)中的光解作用导致形成碳氢键活化产物(η- C6 Me 6 Os(CO)(R)(H)(6a–6c中,R = C 6 H 5,C 6 H 11和CH 2 C(CH 3)3)和游离的六甲基苯。描述了氢化物6a-6c的独立合成以及配合物(η- C6 Me 6)Os(CO)(R)2(4a-4c)和(η- C6 Me 6)Os(CO)的合成)(R)Cl(5a-5c)。(η- C6 Me 6)Os(CO)(环己基)2(4b的结构报道了通过单晶X射线衍射测定的)。
Total Synthesis, Revised Structure, and Biological Evaluation of Biyouyanagin A and Analogues Thereof
作者:K. C. Nicolaou、T. Robert Wu、David Sarlah、David M. Shaw、Eric Rowcliffe、Dennis R. Burton
DOI:10.1021/ja802805c
日期:2008.8.1
compounds. The total synthesis proceeded through cascade sequences that efficiently produced enantiomerically pure key building blocks 15b (ent-zingiberene) and 18 (hyperolactoneC) and featured a novel [2 + 2] photoinduced cycloaddition reaction which occurred with complete regio- and stereoselectivity. Biological investigations with the synthesized biyouyangagins A (2-11) and hyperolactonesC (12-16) revealed
从金丝桃属植物 H. chinese L. var. 中分离。在 NMR 光谱分析的基础上,杨柳、biyouyanagin A 被指定为结构 1a 或 1b。这种新型天然产物表现出显着的抗 HIV 特性并抑制脂多糖诱导的细胞因子产生。本文描述了 biyouyanagin A 和几种类似物 (3-11) 的全合成、biyouyanagin A 到 2b 的结构修订,以及所有合成化合物的生物学特性。全合成通过级联序列进行,该序列有效地产生对映体纯的关键构建块 15b(ent-zingiberene)和 18(超内酯 C),并具有新颖的 [2 + 2] 光诱导环加成反应,该反应具有完全的区域和立体选择性。