The Study of Nucleophlic and Electrohilic Reaсtions of Bis- and 3-Substituted Chroman-2, 4-Dions

Abstract

Aims: Here we study nucleophilic and electrophilic reactions of bis- and condensed 3-substituted chroman-2,4-dions to produce polychromeno (thio)pyrans and trioxaoxonium benzonaphthotetracene salts. Place and Duration of Study: Saratov State University, Chemistry Institute, between September 2011 and July 2012. Results: Reactions of phenylmethylene bis-chroman-2,4-dion, 3-substituted chroman-2, 4-dion with nucleophilic and electrophilic reagents were studied. Intramolecular O-heterocyclization to polyheteronuclear systems with key chromeno (thio) pyrano fragments of various saturation degrees is shown to be characteristic of the compounds studied. It is noted that phenylmethylene bis chroman-2,4-dion, under the action of phosphorus pentasulfide and hydrogen sulfide in situ, forms bis chromeno thiopyrans. Conclusion: Optimal heterocyclization conditions for 3-substituted chroman-2,4-dion with boron trifluoride etherate to trioxaoxonium benzonaphthotetracene salts were found.