微波辅助三组分偶联-S N Ar(CASNAR)序列使4 H -thiopyran -4-ones退火†
摘要:
微波辅助偶合-S N Ar(CASNAR)序列从容易获得的(杂)芳酰氯开始,以高收率容易地合成了全系列的4 H-硫代吡喃-4-酮作为核心结构单元。炔烃和九水合硫化钠在连续的一锅三组分反应中。所有代表在质子化时均显示出吸收带的明显的光致变色性。根据DFT计算,退火的4 H-硫吡喃-4-酮的电子基态具有相当大的两性离子特征。
Synthesis of 2-sulfenylindenones by visible-light-mediated addition of sulfur-centered radicals to 1,3-diarylpropynones
作者:Chengqun Chen、Qian Xiong、Jie Wei
DOI:10.1080/00397911.2019.1580744
日期:2019.3.19
Abstract A novel, visible-light-mediated method for the synthesis of 2-sulfenylindenones from easily available thiophenols (2.0 equiv.) and 1, 3-diarylpropynones (1.0 equiv.) in the presence of eosin Y (0.02 equiv.) under air atmosphere has been developed. The reaction proceeded smoothly, for a wide range of derivatives of thiophenols and 3-diarylpropynones, to give the expected products in moderate
The metal-free oxidative alkene methylation/alkynylation of 1,4-enyn-3-ols with an organic peroxide as the methyl source has been developed, which provides straightforward and practical access to the challenging quaternary-carbon-containing but-3-yn-1-ones. The method is reasoned to go through methylation of functional alkenes utilizing dicumyl peroxide as the methylating reagent and subsequent intermolecular
Sunlight-Driven Decarboxylative Alkynylation of α-Keto Acids with Bromoacetylenes by Hypervalent Iodine Reagent Catalysis: A Facile Approach to Ynones
作者:Hui Tan、Hongji Li、Wangqin Ji、Lei Wang
DOI:10.1002/anie.201503479
日期:2015.7.13
A novel and practical decarboxylativealkynylation of α‐keto acids with bromoacetylenes is catalyzed by hypervalent iodine(III) reagents when irradiation by sunlight at room temperature. The product ynones are generated in good yields. Experiments show that results obtained with blue light (λ=450–455 nm) are comparable to those obtained when using sunlight. Mechanistic studies demonstrate that the
iron(III)-catalyzed synthesis of substituted β-chlorovinyl ketones and α,β-alkynyl ketones from terminal and silyl-substituted alkynes with acidchlorides, respectively, is described. This method features easily available starting materials, a cheap and non-toxic catalyst, simple manipulation and mild reaction conditions. Evidence shows that the catalytic addition of the acidchloride to a terminal alkyne
Nitromethane as a Carbanion Source for Domino Benzoannulation with Ynones: One‐Pot Synthesis of Polyfunctional Naphthalenes and a Total Synthesis of Macarpine
applicability has been devised for the regioselective synthesis of polyfunctional naphthalenes by employing nitromethane and ortho‐haloaryl ynones. Utilization of nitromethane as a one carbon carbanion source that is incorporated into a variety of ynones, ends up as an aromatic nitro substituent. The application of this domino process towards a total synthesis of the polycyclic alkaloid macarpine demonstrate
的单釜,过渡金属-自由,多米诺迈克尔/ S Ñ普遍适用性的Ar协议已经通过使用硝基甲烷和设计用于多官能萘的区域选择性合成邻-haloaryl ynones。硝基甲烷作为一种碳碳负离子源的使用,并被引入到各种炔酮中,最终以芳族硝基取代基的形式出现。该多米诺法在多环生物碱马卡平的全合成中的应用证明了该方法的有效性。在概念上是简单的方法来影响ynones显示广泛的底物范围和官能团耐受性,并已与被取代的硝基甲烷实现的区域选择性,多功能benzoannulation以及与脂环ö-单倍体。