BF2-bound chromophore-containing (NN)-N-boolean AND Pt(II) bisacetylide complex and its application as sensitizer for triplet-triplet annihilation based upconversion

Difluoroboron (BF2) bound phenylacetylide was attached to the Pt(II) center of (NN)-N-boolean AND Pt(II) bisacetylide complex (Pt-1). Enhanced absorption in the visible region (epsilon = 1.37 x 10(4) M-1 cm(-1) at 434 nm) and emissive (IL)-I-3 excited state (tau = 0.92 mu s, Phi = 3.3%) were observed for Pt-1, compared to the model complex dbbpy Pt(II) bisphenylacetylide (Pt-2, tau = 0.90 ms, Phi = 40.0%. dbbpy = 4,4'-di-tertbutyl- 2,2'-bipyridine). Pt-1 was used as the triplet sensitizer for triplet-triplet annihilation (TTA) based upconversion and an upconversion quantum yield (Phi(UC)) of 8.9% was observed with 9,10-diphenylanthracence (DPA) as the triplet acceptor. In comparison, no upconversion was observed for the model complex Pt-2.