title: Helicenes from diarylmaleimides.
abstract: Perkin condensations of arylglyoxylic acids with arylacetic acids, followed by the addition of alkylamine, yield diarylmaleimides in a one-pot procedure. The arylglyoxylic acids are obtained by arene acylation with ClCOCO2Et and reduced with NaI and hypophosphorous acid to the arylacetic acids. With 2,7-di-tert-butyl-pyren-4-yl or chrysen-6-yl as the aryl, photocyclodehydrogenation of the diarylmaleimides yields substituted helicenes which can be reduced to stable anions. The helicenes combine bathochromically shifted absorption with hypsochromically shifted fluorescence with respect to their precursors.
authors.affiliation: Centre de Recherche Paul Pascal, CNRS & Université de Bordeaux , 115 avenue Schweitzer, 33600 Pessac, France.
authors.forename: Harald
authors.initials: H
authors.lastname: Bock
authors.forename: Daniel
authors.initials: D
authors.lastname: Subervie
authors.forename: Pierre
authors.initials: P
authors.lastname: Mathey
authors.forename: Anirban
authors.initials: A
authors.lastname: Pradhan
authors.forename: Parantap
authors.initials: P
authors.lastname: Sarkar
authors.forename: Pierre
authors.initials: P
authors.lastname: Dechambenoit
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Hillard
authors.forename: Fabien
authors.initials: F
authors.lastname: Durola