(NH4)2S2O8-Mediated Diiodination of Alkynes with Iodide in Water: Stereospecific Synthesis of (E)-Diiodoalkenes
摘要:
A new approach to the stereospecific diiodination of alkynes under mild conditions has been developed. This protocol employs ammonium persulfate as an oxidant and iodide as an iodine source, and provides a highly efficient and general method for the preparation of a broad range of (E)-diiodoalkenes in water.
Regioselective Synthesis of 2,3,4-Trisubstituted Pyrroles via Pd(II)-Catalyzed Three-Component Cascade Reactions of Amines, Alkyne Esters, and Alkenes
作者:Xu Zhang、Xuefeng Xu、Gong Chen、Wei Yi
DOI:10.1021/acs.orglett.6b02325
日期:2016.10.7
three-component cascade reaction of diverse amines, alkyne esters, and alkenes is disclosed for the direct synthesis of diverse 2,3,4-trisubstituted pyrroles with broad functional group tolerance and in good to excellent yields. This transformation is supposed to proceed through the cascade formation of C(sp2)–C(sp2) and C(sp2)–N bonds via Pd(II)-catalyzed regioselective alkene migratory insertion, intramolecular
Selective Synthesis of Dihydrophenanthridine and Phenanthridine Derivatives from the Cascade Reactions of <i>o</i>-Arylanilines with Alkynoates through C–H/N–H/C–C Bond Cleavage
作者:Yuanshuang Xu、Caiyun Yu、Xinying Zhang、Xuesen Fan
DOI:10.1021/acs.joc.1c00256
日期:2021.4.16
unprecedented selective synthesis of dihydrophenanthridine and phenanthridinederivatives through the cascade reactions of 2-arylanilines with alkynoates is presented. Mechanistic studies showed that the formation of the dihydrophenanthridine scaffold involves an initial C(sp2)–H alkenylation of 2-arylaniline with alkynoate followed by an intramolecular aza-Michael addition. When this reaction is carried out
Rhodium-Catalyzed Regioselective Domino Azlactone-Alkyne Coupling/Aza-Cope Rearrangement: Facile Access to 2-Allyl-3-oxazolin-5-ones and Trisubstituted Pyridines
作者:Jinqiang Kuang、Shaista Parveen、Bernhard Breit
DOI:10.1002/anie.201704022
日期:2017.7.10
Rhodium‐catalyzedregioselective addition of azlactones to internal alkynes combined with aza‐Cope rearrangement provides efficient atom economic access to 2‐allyl‐3‐oxazolin‐5‐one derivatives. Extension to a triple domino process, in which the above process is combined with in situ azlactone formation starting from amino acids renders this process even more attractive. Subsequent thermolysis of the
Iron-Catalyzed Indolizine Synthesis from Pyridines, Diazo Compounds, and Alkynes
作者:Tim Douglas、Anca Pordea、James Dowden
DOI:10.1021/acs.orglett.7b03252
日期:2017.12.1
The iron(III)-catalyzed synthesis of indolizines from commercially available alkyne, pyridine, and diazo precursors is reported. This mild, expedient method is tolerant of various solvents and proceeds with as little as 0.25 mol % [Fe(TPP)Cl]. Significantly, this multicomponent reaction is compatible with electrophilic alkynes; control experiments demonstrate the importance of the catalyst in promoting
Acetylenic esters. Part III. Reactions of thiocarbonyl compounds with methyl propiolate, methyl methylpropiolate, and methyl phenylpropiolate
作者:G. Dallas、J. W. Lown、J. C. N. Ma
DOI:10.1039/j39680002510
日期:——
Non-terminal acetylenic esters react with many thiocarbonyl compounds to form heterocycles or 1 : 1 addition products. Propiolic esters in most cases form isomeric mixtures of dimethyl 3,3′-thiodiacrylates (I). The stereochemical course of the thiolic nucleophilic additions may be controlled for preparative purposes by changes in solvent polarity. All three stereoisomers of (I) have been prepared.