An efficient route for the synthesis of novel thioether containing dihydropyrano[2,3-c]pyrazoles has been accomplished via a solvent-free, catalyst-free, one-pot, five component domino strategy. This synthetic approach offers several advantages such as an easy work-up, no need for purification techniques and a short reaction time with good atom economy and high yields of the products (81–86%).
通过无溶剂,无催化剂,一锅,五组分多米诺骨牌策略,已经成功地完成了一种新型的含有二氢吡喃并[2,3- c ]吡唑的硫醚合成方法。这种合成方法具有许多优点,例如后处理容易,无需纯化技术,反应时间短,原子经济性好,产物收率高(81-86%)。
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2-C-H Acetoxylation of Diversely Substituted (<i>E</i>
)-1-(Arylmethylene)-2-phenylhydrazines Using PhI(OAc)<sub>2</sub>
as Acetoxy Source at Ambient Conditions
作者:Goutam Brahmachari、Indrajit Karmakar
DOI:10.1002/ejoc.201900994
日期:2019.9.15
It's Simple! Catalyst‐ and additive‐free regioselective direct sp2 C–H acetoxylation of biologically interesting aldehyde hydrazones to access a new series of hydrazone acetates has been achieved. The reaction proceeds at ambient temperature employing PIDA as an acetoxy source.
I<sub>2</sub>/DMSO-Promoted Synthesis of Diaryl Sulfide- and Selenide-Embedded Arylhydrazones
作者:Arun Dhurey、Subhro Mandal、Animesh Pramanik
DOI:10.1021/acs.joc.2c02974
日期:2023.5.5
derivatization of arylhydrazones are important in pharmaceutical, medicinal, material, and coordination chemistry. In this regard, a facile I2/DMSO-promoted cross-dehydrogenative coupling (CDC) for direct sulfenylation and selenylation of arylhydrazones has been accomplished utilizing arylthiols/arylselenols at 80 °C. This method provides a metal-free benign route for the synthesis of a variety of arylhydrazones
芳基腙的功能化和衍生化在制药、医药、材料和配位化学中具有重要意义。在这方面,在 80 °C 下利用芳基硫醇/芳基硒醇完成了用于芳基腙直接硫化和硒基化的简便I 2 /DMSO 促进的交叉脱氢偶联 (CDC)。该方法为合成各种嵌入不同二芳基硫化物和硒化物部分的芳基腙提供了一种无金属的良性途径,收率从高到高。在该反应中,分子 I 2充当催化剂,DMSO 用作温和氧化剂和溶剂,通过 CDC 介导的催化循环生成多种硫基和硒基芳基腙。
Efficient Synthesis of Fully Substituted and Diversely Functionalized Pyrazoles through <i>p</i>‐TSA Catalyzed One‐Pot Condensation of Cyclic <i>β</i>‐Diketones, Arylglyoxals and Arylhydrazones
作者:Arun Dhurey、Subhro Mandal、Animesh Pramanik
DOI:10.1002/ejoc.202300770
日期:2023.10.21
An acid catalyzed one-pot condensation of readily available cyclic β-diketones, arylglyoxals and arylhydrazones produces a library of diverselyfunctionalized pyrazole derivatives in excellent yield under metal-catalyst-free benign conditions.
Organocatalytic asymmetric hydroarylation of o-hydroxyl styrenes via remote activation of phenylhydrazones
作者:Wei Dai、Han Lu、Xiao-Li Jiang、Ting-Ting Gao、Feng Shi
DOI:10.1016/j.tetasy.2014.12.009
日期:2015.2
The first catalytic asymmetric styrene hydroarylation reaction has been established via the enantioselective Friedel-Crafts alkylations of phenylhydrazones with o-hydroxyl styrenes under the catalysis of a chiral phosphoric acid as an organocatalyst, leading to the construction of a chiral 1,1-diarylethane scaffold with high enantioselectivity (up to 89% ee). The investigation on the activation mode suggested that the two reactants, o-hydroxyl styrenes and phenylhydrazones, were simultaneously activated by the catalyst via multiple hydrogen-bonds. The remote activation of the hydrazone functionality by a dual hydrogen-bonding interaction with the catalyst contributed greatly to the hydroarylation reaction of the o-hydroxyl styrenes. (C) 2014 Elsevier Ltd. All rights reserved.