Asymmetric Annulation of 3-Alkynylacrylaldehydes with Styrene-Type Olefins by Synergetic Relay Catalysis from AgOAc and Chiral Phosphoric Acid
作者:Hao Zhang、Le Zhu、Shaozhong Wang、Zhu-Jun Yao
DOI:10.1021/jo501196n
日期:2014.8.1
Asymmetric annulation of 3-alkynylacrylaldehydes with 2-hydroxystyrenes has been studied and achieved by synergetic catalysis from AgOAc and chiral phosphoric acid, providing the corresponding multiring products with decent total yields and moderate to excellent enantioselectivities (up to 95% ee). The developed mild multibond-formation cascade reaction involves in situ generation of pyrylium intermediate
Enantioselective Synthesis of Cyclopentadienes by Gold(I)- Catalyzed Cyclization of 1,3-Dien-5-ynes
作者:Ana M. Sanjuán、Patricia García-García、Manuel A. Fernández-Rodríguez、Roberto Sanz
DOI:10.1002/adsc.201300448
日期:2013.7.8
An asymmetric synthesis of elusive chiral cyclopentadienes has been developed by gold(I)‐catalyzed alkoxycyclization of 1,3‐dien‐5‐ynes. The application of these substrates in completely diastereoselective Diels–Alder cycloaddition reactions, which can be carried out in onepotfrom achiral 1,3‐dien‐5‐ynes, allows the preparation of highly functionalized products bearing five stereogenic centers with
Imidazolidine Hydride Donors in Palladium-Catalyzed Alkyne Hydroarylation
作者:Soe L. Tun、S. V. Santhana Mariappan、F. Christopher Pigge
DOI:10.1021/acs.joc.2c00725
日期:2022.6.17
were converted to trisubstituted alkenes via a syn hydroarylation process, while a terminal alkyne was converted to a cis alkene via a formal trans hydroarylation reaction. Benzanilide products could be converted to carboxylic acidderivatives under basic conditions, resulting in the net conversion of alkynyl aldehydes to alkenyl carboxylic acids. A styrene derivative with an attached N,N′-dimethylbenzimidazoline
醛衍生的咪唑烷作为氢化物供体参与分子内还原 Heck 型反应。由邻-炔基苯甲醛制备的N , N ' -二苯基咪唑烷经过区域选择性和立体选择性钯催化加氢芳基化,然后进行形式 1,5-氢化物转移和还原消除,得到取代的烯烃和咪唑部分,后者方便地原位转化为环-打开苯甲酰苯胺以简化产品分离。内部炔烃通过顺式加氢芳基化过程转化为三取代烯烃,而末端炔烃通过形式反式转化为顺式烯烃加氢芳基化反应。苯甲酰苯胺产物可以在碱性条件下转化为羧酸衍生物,导致炔基醛净转化为烯基羧酸。还发现具有连接的N,N'-二甲基苯并咪唑啉氢化物供体的苯乙烯衍生物经历类似的氢化芳基化/苯并咪唑啉氧化,得到二芳基乙烷产物。
Synthesis of N-Acyl Pyrroles and Isoindoles from Oxime Ester Precursors via Transition-Metal-Catalyzed Iminocarboxylation
作者:Daesung Lee、Siyuan Su
DOI:10.1055/s-0042-1751377
日期:——
3-enyne and an ortho-alkynylarene moiety, followed by a spontaneous O→N acyl migration of the enol carboxylate intermediate to generate N-acyl pyrroles and isoindoles. The reaction scope for pyrrole synthesis is general, whereas the formation of isoindoles has a relatively narrow scope because of their instability.
Ethene‐1,1‐disulfonyl Difluoride (EDSF) for SuFEx Click Chemistry: Synthesis of SuFExable 1,1‐Bissulfonylfluoride Substituted Cyclobutene Hubs
作者:Christopher J. Smedley、Marie‐Claire Giel、Thomas Fallon、John E. Moses
DOI:10.1002/anie.202303916
日期:2023.7.24
Ethene-1,1-disulfonyl difluoride (EDSF) represents a novel SuFEx connector hub. Here, we demonstrate the [2+2] cycloaddition reaction of EDSF with aryl acetylenes, which rapidly and regioselectively generates unique 1,1-bissulfonylfluoride substituted cyclobutenes. Moreover, these products can selectively undergo SuFEx reactions with phenols, highlighting their potential for constructing complex molecular