10075-47-5Relevant academic research and scientific papers
3-Homoacyl coumarin: An all carbon 1,3-dipole for enantioselective concerted (3+2) cycloaddition
Chen, Yi-Ru,Ganapuram, Madhusudhan Reddy,Hsieh, Kai-Hong,Chen, Kai-Han,Karanam, Praneeth,Vagh, Sandip Sambhaji,Liou, Yan-Cheng,Lin, Wenwei
, p. 12702 - 12705 (2018)
A new type of all-carbon 1,3-dipole precursor, 3-homoacylcoumarin, was employed for the stereoselective (3+2) cycloaddition with indandione alkylidenes to generate a series of coumarin/indandione-fused spirocyclopentanes bearing four contiguous stereogenic centers. While two reaction pathways progressed simultaneously, detailed mechanistic investigation revealed that the highly efficient stereoselective concerted route dominated the extremely slow stepwise pathway.
Enantioselective Construction of Spirooxindole-Fused Cyclopenta[c]chromen-4-ones Bearing Five Contiguous Stereocenters via a Stepwise (3+2) Cycloaddition
Vagh, Sandip Sambhaji,Karanam, Praneeth,Liao, Cheng-Chieh,Lin, Ting-Han,Liou, Yan-Cheng,Edukondalu, Athukuri,Chen, Yi-Ru,Lin, Wenwei
, p. 1679 - 1685 (2020)
The bifunctional quinine-catalyzed stepwise (3+2) cycloaddition for the enantioselective construction of spirooxindole-fused cyclopenta[c]chromen-4-ones is developed. The reactions of 3-homoacylcoumarins and alkylidene oxindole electrophiles generate aforementioned spirooxindole-chromenone adducts bearing five contiguous stereocenters, of which one is the spiro all-carbon quaternary stereocenter in high yields (up to 99%) with excellent stereoselectivities (up to >20:1 dr and 99% ee). This methodology was investigated for three different alkylidene oxindole electrophiles and could also be practically demonstrated on a gram scale. Mechanistic investigations revealed that the (3+2) cycloaddition for the enantioselective synthesis of spirooxindole-fused cyclopenta[c]chromen-4-ones is proceeding via a stepwise reaction pathway. (Figure presented.).
Enantioselective Synthesis of Spiropyrazolone-Fused Cyclopenta[ c]chromen-4-ones Bearing Five Contiguous Stereocenters via (3+2) Cycloaddition
Khairnar, Pankaj V.,Su, Yin-Hsiang,Edukondalu, Athukuri,Lin, Wenwei
, p. 12326 - 12335 (2021/08/24)
An enantioselective synthesis of spiropyrazolone-fused cyclopenta[c]chromen-4-ones is demonstrated via a (3+2) cycloaddition reaction. The reactions of 3-homoacylcoumarins and α,β-unsaturated pyrazolones in the presence of the cinchona-alkaloid derived hy
Preparation method of benzofurocoumarin compound
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Paragraph 0051-0055; 0059; 0061, (2020/11/23)
The invention discloses a preparation method of a photoactive benzofurocoumarin compound. The photoactive benzofurocoumarin compound is a compound shown as a formula I; the enantioselectivity of the compound shown in the formula I is up to 95-99%. The pho
Ir(ppy)3-Catalyzed, Visible-Light-Mediated Reaction of α-Chloro Cinnamates with Enol Acetates: An Apparent Halogen Paradox
F?ll, Thomas,Rehbein, Julia,Reiser, Oliver
supporting information, p. 5794 - 5798 (2018/09/13)
The visible-light-mediated activation of vinyl chlorides derived from α-chloro ethyl cinnamates via oxidative quenching of excited photocatalyst fac-Ir(ppy)3 is described. Upon photoelectron transfer and chloride extrusion, the corresponding vinyl radical can be efficiently trapped by enol acetates, giving rise to synthetically useful 1,4-dicarbonyl compounds in good to excellent yields. This transformation is distinguished by mild and environmentally benign reaction conditions and can be performed on a multigram scale, in sharp contrast to contrasting α-bromo ethyl cinnamates, which show low conversion under the various conditions applied.
Coumarinyl(thienyl)thiazoles as new fluorescent molecular photoswitches
Bochkov,Yarovenko,Barachevskii,Nabatov,Krayushkin,Dolotov,Traven',Beletskaya
scheme or table, p. 162 - 169 (2010/06/12)
A number of new photochromic 3-(4-phenylthiazol-5-yl)-and 3-(4-hetarylthiazol-5-yl)- coumarins has been synthesized. These compounds possess properties of molecular photo- switches providing a reversible change of the fluorescence intensity in the visible
Synthesis and photoinduced fluorescence of 3-(2-hetarylethenyl)chromen-2- ones
Bochkov,Yarovenko,Krayushkin,Chibisova,Valova,Barachevskii,Traven',Beletskaya
experimental part, p. 595 - 601 (2009/04/11)
3-(2-Hetarylethenyl)chromen-2-ones were synthesized for the first time, following two different schemes, and their spectral and photochemical properties were studied. The title compounds were found to undergo both reversible and irreversible photoinduced
