Arylation of diethyl malonate and ethyl cyanoacetate catalyzed by palladium/di-tert-butylneopentylphosphine
作者:Jeffrey G. Semmes、Stephanie L. Bevans、C. Haddon Mullins、Kevin H. Shaughnessy
DOI:10.1016/j.tetlet.2015.01.072
日期:2015.6
α-Arylated carbonyl derivatives are important structural motifs in many natural products and pharmaceutically active compounds. Although arylation of simple monocarbonyl compounds is a well-established methodology, metal-catalyzed arylation of β-dicarbonyl derivatives is significantly more challenging. The ability of β-dicarbonyl anions to bind to palladium in a κ2-O,O mode, rather than the κ1-C-bound
在许多天然产物和药物活性化合物中,α-芳基化羰基衍生物是重要的结构基序。尽管简单的单羰基化合物的芳基化是一种公认的方法,但金属催化的β-二羰基衍生物的芳基化更具挑战性。β二羰基的阴离子结合至钯在κ的能力2 - ø,ö模式,而不是κ 1 - c ^结合的模式键形成所需的,经常导致催化剂体系的失活。烯醇盐的C-结合形式可通过使用空间需求的配体来促进。在此,我们报告中指出,空间要求的二叔丁基丁基新戊基膦(DTBNpP)配体与Pd(dba)2结合为芳基溴化物和氯化物与丙二酸二乙酯的偶联提供了有效的催化剂。Pd / DTBNpP系统还催化芳基溴化物与氰基乙酸乙酯的偶联。
An Efficient and Mild CuI/<scp>l</scp>-Proline-Catalyzed Arylation of Acetylacetone or Ethyl Cyanoacetate
作者:Yongwen Jiang、Nan Wu、Haihong Wu、Mingyuan He
DOI:10.1055/s-2005-918921
日期:——
The coupling reaction of aryl iodides with acetylacetone or ethyl cyanoacetate under catalysis of CuI/l-proline works at relatively mild conditions to provide 3-aryl-2, 4-pentanediones and α-aryl cyanoacetates in moderate to good yields.
Ethyl Cyanoacetate: A New Cyanating Agent for the Palladium-Catalyzed Cyanation of Aryl Halides
作者:Shuyan Zheng、Chunhui Yu、Zhengwu Shen
DOI:10.1021/ol3014914
日期:2012.7.20
A new Pd-catalyzed cyanation reaction has been discovered using ethyl cyanoacetate as the cyanating reagent. A variety of electron-rich and electron-deficient aryl halides were efficiently converted into their corresponding nitriles in good to excellent yields.
Visible Light instead of Transition Metal: Electron Donor Acceptor Complex Enabled Cross‐Coupling of Aryl Halides with Active Methylene Compounds
作者:Alexey A. Volkov、Dmitry I. Bugaenko、Alexander V. Karchava
DOI:10.1002/adsc.202301192
日期:2024.2.19
An arylation of anions of activemethylene compounds with aryl halides provides an access to synthetically versatile α-arylated 1,3-diketones, β-keto esters, β-keto nitriles, β-cyano esters, etc. Previously, these C−C cross-coupling reactions have been accomplished only using transition metal-based catalysts. Herein, we demonstrate that these arylations can be successfully realized under catalyst-free
活性亚甲基化合物的阴离子与芳基卤化物的芳基化提供了合成通用的 α-芳基化 1,3-二酮、β-酮酯、β-酮腈、β-氰基酯等的途径。以前,这些 CC 交叉-偶联反应仅使用过渡金属基催化剂即可完成。在此,我们证明这些芳基化可以在无催化剂条件下采用电子供体-受体(EDA)复合物光活化策略成功实现。该方案进一步优化,用于通过分子内 C−C 偶联半一锅合成吲哚衍生物。
A rational design strategy of radical-type mechanophores with thermal tolerance
. A combined experimental and theoretical analysis revealed that the high thermal tolerance of these RMs is related to the radical-stabilization energy (RSE) as well as the Hammett and modified Swain–Lupton constants at the para-position (σp). The trend of the RSE values is in good agreement with the experimentally evaluated thermal tolerance of a series of mechanoresponsive RMs based on the bisarylcyanoacetate