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Pd/Cu-Catalyzed Desulfitative Coupling Cyclization Of Ketene Dithioacetals With Terminal Alkynes:Synthesis Of Multi-substituted Furan Derivatives

Posted on:2017-04-04Degree:MasterType:Thesis
Country:ChinaCandidate:P ChenFull Text:PDF
GTID:2311330485459945Subject:Organic Chemistry
Abstract/Summary:PDF Full Text Request
Because of its advantages in diverse structures and convenient synthesis methods ketene dithioacetals has attracted more and more chemical workers to develop unique C-C bond-forming methods. Ketene dithioacetals is a representative compound among organosulfur compounds, and our group has been engaged in it. Based on our previous reports about the transition metal catalyzed C-S bond activation of ketene dithioacetals, the thesis provided a novel application of ketene dithioacetals as a electrophilic coupling partener.This thesis mainly includes the following parts:1. Two aspects has been reviewed herein. (1) the research about coupling of organosulfur compounds with boric acid, olefin and alkyne was summaried. (2) the electrophilic cyclization of the conjugated ene-yne-ketones under Cr, Zn, Pd and Cu catalyzed was summarized.2. The reaction mechanism undergoes a two-step cyclic process (1) ketene dithioacetals reacts with arylacetylene, which undergoes Sonogashira type reaction and then generates conjugated ene-yne-ketones intermediate containing alkylthio group and (2) the ene-yne-ketones is transformed into metal carbene and then is oxidized by oxygen in the air.3.20 multi-substituted furan derivatives with alkylthio functional groups were synthesized through the catalytic system designed and their'H NMR,13C NMR and mass spectra are characterized.4. A novel method from a,a-dicarbonyl ketene dithioacetals was developed to synthesis multi-substituted furan derivatives...
Keywords/Search Tags:Ketene Dithioacetals, C-S Bond Activation, Ene-yne-ketones, Furan Derivatives
PDF Full Text Request
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