Chalcogenation/pyrrolo(pyrido)annulation of 2-(3-butenyl)quinazolin-4(3H)-ones by arylsulfenyl(selenyl) chlorides. (9th April 2022) - Vaskevych, Alla I.
Abstract: Arylsulfenyl chlorides react with 2-(3-butenyl)quinazolinones in dichloromethane by the AdE addition mechanism to give 2-(3-arylthio-4-chlorobutyl)quinazolin-4 (3 Н )-ones, which, when heated in the presence of sodium acetate, cyclize to 8-arylthio-6, 7, 8, 9-tetrahydropyrido [2, 1- b ]quinazolin-11-ones. Arylsulfenylation (selenylation) of 2-(3-butenyl)quinazolinones conducted in nitromethane in the presence of an equimolar amount of lithium perchlorate proceeds as an electrophilic 5- exo-trig cyclization involving either of the nitrogen atoms of the quinazolone nucleus to yield 1-arylthio (selenyl)methyl substituted angular-annulated 2, 3-dihydropyrrolo [1, 2- a ]quinazolin-5(1 H )-ones as major products and isomeric linear-annulated 2, 3-dihydropyrrolo [2, 1- b ]quinazolin-9(1 H )-one derivatives as minor products. Graphical abstract: Image 1