Design, synthesis, characterization, luminescence and non-linear optical (NLO) properties of multinuclear platinum(ii) alkynyl complexes

Abstract

A series of luminescent multinuclear platinum(II) alkynyl complexes containing triethynylbenzene or 1,4-bis(3,5-diethynylphenyl)buta-1,3-diyne as cores has been successfully synthesized and characterized. The electronic absorption, emission, nanosecond transient absorption and electrochemical properties of these complexes have been reported. These complexes show long-lived emissions in degassed benzene solution and in alcoholic glass at 77 K. Moreover, they are found to exhibit two-photon absorption (2PA) and two-photon induced luminescence (TPIL) properties, and their two-photon absorption cross-sections have been determined to be 6-191 GM upon excitation at 720 nm. Through a systematic comparison, it has been found that tetra- and hexanuclear platinum(II) complexes show better 2PA and TPIL properties than their di- and trinuclear counterparts.

Accessing the Long-Lived Triplet Excited States in Transition-Metal Complexes: Molecular Design Rationales and Applications

“…The photophysical properties of the coordinated Bodipy ligand are also dependent on the auxiliary ligands. For instance, trans ‐bis(trialkylphosphine) Pt(II) acetylide complexes are of particular interest because different acetylide ligands can be introduced into the molecular structure by a stepwise approach . We prepared Bodipy‐containing Pt(II) complexes (Figure ) .…”

Broadband Visible‐Light‐Harvesting trans‐Bis(alkylphosphine) Platinum(II)‐Alkynyl Complexes with Singlet Energy Transfer between BODIPY and Naphthalene Diimide Ligands

“…[28] Conventional Pt II , Ru II , and Ir III complexes usually show weak absorption in the visible spectral region. [2,14,[27][28][29][30] For example, N^N-Pt II bisacetylide complexes, [10,12,31] or trans-bis(alkylphosphine) platinum(II)-alkynyl complexes, [8,32,33] usually show molar absorption coefficients smaller than 10 000 m À1 cm À1 in the visible spectral region. This is also true to a large extent for other Ru II , Pt II , Re I , or Ir III complexes.…”

trans-Bis(alkylphosphine) platinum(ii)-alkynyl complexes showing broadband visible light absorption and long-lived triplet excited states

“…13 On the other hand, the trans-bis(alkylphosphine) platinum(II)alkynyl complexes have attracted much attention. 5,[19][20][21][22][23][24] The molecular structure of these compounds can be easily modied by using different acetylide ligands, providing tunability of both the photophysical and redox properties. 1, 19 However, trans-bis(alkylphosphine) platinum(II)-alkynyl complexes showing strong visible light absorption were rarely reported.…”

“…Our method is exemplied with two heteroleptic trans-bis(alkylphosphine) platinum(II)-alkynyl complexes (Pt-1 and Pt-2, Scheme 1). 5,[19][20][21][22][23][24] For transition metal complexes containing multi-chromophores to achieve broadband absorption of visible light, it is important to control the direction of the singlet energy transfer so that the spin converter acts as the singlet energy acceptor to ensure efficient transformation of the photoexcitation energy into triplet state energy. 13b, 28,29 Herein we prepared two heteroleptic trans-bis(alkylphosphine) platinum(II)-alkynyl complexes (Pt-1 and Pt-2, Scheme 1).…”