title: Donor-functionalized polydentate pyrylium salts and phosphinines: synthesis, structural characterization, and photophysical properties.
abstract: A series of donor-functionalized pyrylium salts have been prepared by classical condensation reactions which were further converted into the corresponding thienyl- and pyridyl-substituted polydentate lambda(3)-phosphinines by reaction with P(SiMe(3))(3). Further chemical modification of these phosphorus heterocycles with Hg(OAc)(2) in the presence of methanol resulted in the formation of lambda(5)-phosphinines. The photophysical properties of a selected series of thienyl- and pyridyl-functionalized pyrylium salts, lambda(3)- and lambda(5)-phosphinines, were investigated and the results compared and supported by theoretical calculations on the DFT level. Significant fluorescence was observed for the pyrylium salts and lambda(5)-phosphinines. In contrast, the heteroaromatic substituted lambda(3)-phosphinines show very little emission which is consistent with the low oscillator strength predicted by DFT calculations for this pi-->pi* transition. Furthermore, all three classes of compounds show readily observable phosphorescence in solution, which was determined by time-gated detection at low temperature.
authors.affiliation: Department of Chemical Engineering and Chemistry, Schuit Institute of Catalysis, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
authors.forename: Christian
authors.initials: C
authors.lastname: Müller
authors.forename: Dorothee
authors.initials: D
authors.lastname: Wasserberg
authors.forename: Jarno J M
authors.initials: JJ
authors.lastname: Weemers
authors.forename: Evgeny A
authors.initials: EA
authors.lastname: Pidko
authors.forename: Sandra
authors.initials: S
authors.lastname: Hoffmann
authors.forename: Martin
authors.initials: M
authors.lastname: Lutz
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Spek
authors.forename: Stefan C J
authors.initials: SC
authors.lastname: Meskers
authors.forename: René A J
authors.initials: RA
authors.lastname: Janssen
authors.forename: Rutger A
authors.initials: RA
authors.lastname: van Santen
authors.forename: Dieter
authors.initials: D
authors.lastname: Vogt
mesh_terms: D018360:Crystallography, X-Ray; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D009943:Organophosphorus Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D010777:Photochemistry; D011714:Pyrans / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D009943:Organophosphorus Compounds; D011714:Pyrans