117316-33-3Relevant academic research and scientific papers
Synthesis of Chromen[4,3-b]pyrrolidines by Intramolecular 1,3-Dipolar Cycloadditions of Azomethine Ylides: An Experimental and Computational Assessment of the Origin of Stereocontrol
Costa, Paulo R. R.,Sansano, José M.,Cossío, Unai,Barcellos, Julio C. F.,Dias, Ayres G.,Nájera, Carmen,Arrieta, Ana,De C?zar, Abel,Cossío, Fernando P.
, p. 4689 - 4698 (2015)
Azomethine ylides, generated from imine-derived O-cinnamyl or O-crotonyl salicylaldeyde and α-amino acids, undergo intramolecular 1,3-dipolar cycloaddition, leading to chromene[4,3-b]pyrrolidines. Two reaction conditions are used: (a) microwave-assisted heating (200 W, 185 °C) of a neat mixture of reagents, and (b) conventional heating (170 °C) in PEG-400 as solvent. In both cases, a mixture of two epimers at the α-position of the nitrogen atom in the pyrrolidine nucleus was formed through the less energetic endo-approach (B/C ring fusion). In many cases, the formation of the stereoisomer bearing a trans-arrangement into the B/C ring fusion was observed in high proportions. Comprehensive computational and kinetic simulation studies are detailed. An analysis of the stability of transient 1,3-dipoles, followed by an assessment of the intramolecular pathways and kinetics are also reported. The two-component synthesis of chromene[4,3-b]pyrrolidines has been achieved under two different conditions. The strategy was used to obtain N-sulfonylated adducts with interesting biological activity. Calculations show that formation of W and S′ 1,3-dipoles determines the stereochemical outcome of the reaction, which involves asynchronous transition structures.
SUBSTITUTED CHROMANES, ANALOGS THEREOF, AND METHODS OF USE AND SYNTHESIS
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Paragraph 0162; 0165-0166; 0168, (2021/01/25)
Disclosed are chromane compounds, analogs thereof, and methods of their synthesis and use. The compounds may be synthesized by methods involving reductive annulations of arylidene malonates with unsaturated electrophiles using photoredox/Lewis acid cooperative catalysis. The compounds may be formulated in a pharmaceutical composition for treating one of the aforementioned diseases or disorders.
PPh3-mediated intramolecular conjugation of alkyl halides with electron-deficient olefins: Facile synthesis of chromans and relevant analogues
Zhu, Jian-Bo,Wang, Peng,Liao, Saihu,Tang, Yong
supporting information, p. 4570 - 4572 (2013/06/04)
With the mediation of phosphine, the direct intramolecular coupling of two electrophiles-alkyl halides with electron-deficient olefins-has been successfully realized in an intramolecular conjugate addition manner. The reaction provides a new approach for
Catalytic intramolecular formal [3 + 2] cycloaddition for the synthesis of benzobicyclo[4.3.0] compounds
Han, Xun,Ye, Long-Wu,Sun, Xiu-Li,Tang, Yong
supporting information; experimental part, p. 3394 - 3397 (2009/09/08)
In the presence of 20 mol % of tributylphosphine, tert-butyl carbonate substrate 3a undergoes smoothly an intramolecular formal [3 + 2] cycloaddition reaction at room temperature to give benzobicyclo[4.3.0] compounds in 99% yield with a 19/81 ratio of 2a
INVESTIGATIONS ON INTRAMOLECULAR CYCLOADDITION REACTIONS OF PHOTOCHEMICALLY GENERATED CARBONYL YLIDES
Brokatzky-Geiger, Juergen,Eberbach, Wolfgang
, p. 1519 - 1524 (2007/10/02)
Upon photoexcitation of appropriately substituted oxiranes ring opening leads to carbonyl ylides which undergo intramolecular cycloaddition reactions affording annelated and/or bridged tetrhydrofurans.
