143565-13-3Relevant academic research and scientific papers
Visible-light induced cascade radical cyclization of sulfinic acids and o-(allyloxy)arylaldehydes towards functionalized chroman-4-ones
Li, Guang-Hui,Han, Qing-Qing,Sun, Yuan-Yuan,Chen, De-Mao,Wang, Zu-Li,Xu, Xin-Ming,Yu, Xian-Yong
, p. 3255 - 3258 (2020)
An efficient method for the synthesis of functionalized chroman-4-ones induced by visible light via the radical cyclization reaction of sulfinic acids and o-(allyloxy)arylaldehydes at room temperature was described. The corresponding products were isolate
Visible Light-Promoted Synthesis of Spiroepoxy Chromanone Derivatives via a Tandem Oxidation/Radical Cyclization/Epoxidation Process
Jung, Sungwoo,Kim, Jiyun,Hong, Sungwoo
, p. 3945 - 3949 (2017)
A highly efficient and straightforward approach for the synthesis of spiroepoxy chroman-4-one derivatives was developed using a visible light-enabled tandem radical strategy. The reaction is initiated by the formation of an acyl radical that undergoes intramolecular radical cyclization and epoxidation. The optimal result was obtained with 1 mol% of Ru(bpy)3Cl2?6H2O, TBHP, and K2CO3 in i-PrOAc at room temperature with irradiation from a blue LED. This unprecedented tandem approach utilizes a broad range of substrates, and provides a convenient and powerful synthetic tool for accessing the synthetically useful spiroepoxy chroman-4-ones and their nitrogen-containing derivatives. (Figure presented.).
Photoinduced free radical chemistry of the acyl tellurides: Generation, inter- and intramolecular trapping, and ESR spectroscopic identification of acyl radicals
Crich, David,Chen, Chen,Hwang, Jae-Taeg,Yuan, Hongwei,Papadatos, Aristotle,Walter, Robert I.
, p. 8937 - 8951 (2007/10/02)
Acyl tellurides are prepared in good to excellent yield by the reaction of sodium aryl tellurides with acyl chlorides, or mixed anhydrides, and are found to be moderately air-stable substances. In contrast to previous literature reports, acyl tellurides of aryl and vinyl carboxylic acids are found to be excellent sources of acyl radicals on photolysis with a simple white light source. The acyl radicals so generated may be trapped intermolecularly by dichalcogenides, or by TEMPO in excellent yield. Trapping by N-tert-butyl-α-phenyl nitrone produces a stable nitroxide radical which has been characterized by ESR spectroscopy. The very efficient trapping of acyl radicals by acyl tellurides themselves is demonstrated by a crossover experiment. Acyl tellurides are shown to participate in very efficient radical cyclization reactions onto alkenes with the formation of five-, six-, and eight-membered rings. The immediate products of the cyclizations onto alkenes are α-[(aryltelluro)methyl] ketones and the chemistry of these relatively unstable species is briefly described. Treatment with hydrogen peroxide affords α-methylene ketones in high yield. When elimination of the aryl telluro group is not possible the α-[(aryltelluro)methyl] ketones are stable species that may subsequently be employed in further radical chain reactions, for example with tributyltin hydride and methyl acrylate. Cyclization onto alkynes yields α-[(aryltelluro)methylene] ketones which are stable species and which take part in substitution reactions with higher order cuprates or with diphenyl diselenide.
