Palladium-Catalyzed Acylation Reactions: A One-Pot Diversified Synthesis of Phthalazines, Phthalazinones and Benzoxazinones
作者:Basuli Suchand、Gedu Satyanarayana
DOI:10.1002/ejoc.201800159
日期:2018.5.24
proceeds through [Pd]‐catalyzed acylation and nucleophilic cyclocondensation with dinucleophilic reagents. This process was based on direct coupling with simple bench‐top aldehydes without the assistance of directing group and without activating the carbonyl group. The process is highly advantageous because it employs simple nitrogen‐based nucleophiles, and non‐toxic and readily accessible aldehydes as the
Synthesis of Tetrasubstituted Pyrazoles from Substituted Hydrazines and β-Keto Esters
作者:Ian J. Bakanas、Gustavo Moura-Letts
DOI:10.1002/ejoc.201601093
日期:2016.11
Herein we report the synthesis of tetrasubstituted pyrazoles from simple hydrazines and β-keto esters under mild, basic conditions. This reaction enables the selective synthesis of pyrazolones, alkoxypyrazoles, and tetrasubstituted pyrazoles for a large variety of aromatic hydrazines and substituted β-keto esters with high yields and selectivities. This method permits access to highly complex pyrazole
Mechanism of a No-Metal-Added Heterocycloisomerization of Alkynylcyclopropylhydrazones: Synthesis of Cycloheptane-Fused Aminopyrroles Facilitated by Copper Salts at Trace Loadings
作者:Sidney M. Wilkerson-Hill、Diana Yu、Phillip P. Painter、Ethan L. Fisher、Dean J. Tantillo、Richmond Sarpong、Jason E. Hein
DOI:10.1021/jacs.7b06007
日期:2017.8.2
heterocycloisomerization reaction that forms annulated aminopyrroles is presented. Density functional theory calculations and kinetic studies suggest the reaction is catalyzed by trace copper salts and that a Z- to E-hydrazone isomerization occurs through an enehydrazine intermediate before the rate-determining cyclization of the hydrazone onto the alkyne group. The aminopyrrole products are obtained in 36-93% isolated
介绍了形成环氨基吡咯的新杂环异构化反应的机理研究。密度泛函理论计算和动力学研究表明,该反应是由痕量铜盐催化的,并且在腙到炔基上的限速环化之前,通过烯肼中间体发生 Z 到 E 腙异构化。取决于炔基取代基的性质,以36-93%的分离产率获得氨基吡咯产物。开发了一种新的自动采样技术以获得可靠的机械数据。
ESTER HYDRAZONES AS POSSIBLE PRECURSORS TO ALKOXYDIAZOALKANES: I. THE SYNTHESIS OF ESTER (<i>p</i>-TOLYLSULFONYL)HYDRAZONES AND THEIR DECOMPOSITION IN PROTIC SOLVENTS TO GIVE MIXED ACETALS
作者:Robert J. Crawford、Rintje Raap
DOI:10.1139/v65-015
日期:1965.1.1
(p-tolylsulfonyl)hydrazone (I) was prepared from the reaction between (p-tolylsulfony1)hydrazide and either methyl benzimidate hydrochloride or methyl orthobenzoate. When the potassium or sodium salt of this hydrazone was deconlposed, ther~nally or photochemically, in the presence of alcohols, benzaldehyde mixed acetals could be isolated in good yields and of high purity. When the decomposition was carried