Disubstituted fluorocyclopropanes for 2-heterosubstituted electron-rich indolizine synthesis

New product type for fluorocyclopropane chemistry was found. gem-Fluorohalocyclopropane ring-opening products — (2-fluoroallyl)pyridinium salts — were found to undergo base-promoted cyclization either with fluorine atom retained or with intermolecular fluorine substitution with additional NuH, producing two- or three component derived 2-F,N,S,O-subtituted indolizines. This strategy allows a wide range of electron-rich 2-heteroindolizines with different nucleophilic part including ones with functional groups capable for coupling with biologically relevant structures. [Сu]-activation of cyclopropane C-X bond allows disubstituted fluorocyclopropane to be involved in the process. 2-Heteroindolizines obtained possess blue-light emission, high intensity in DMSO, good Stokes shift and noticeable quantum yield.