Donor-functionalized polydentate pyrylium salts and phosphinines: synthesis, structural characterization, and photophysical properties.
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.
Müller
Christian
C
Department of Chemical Engineering and Chemistry, Schuit Institute of Catalysis, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
Wasserberg
Dorothee
D
Weemers
Jarno J M
JJ
Pidko
Evgeny A
EA
Hoffmann
Sandra
S
Lutz
Martin
M
Spek
Anthony L
AL
Meskers
Stefan C J
SC
Janssen
René A J
RA
van Santen
Rutger A
RA
Vogt
Dieter
D
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
D009943:Organophosphorus Compounds; D011714:Pyrans