Experimental details and spectroscopic data of [(PtThpyCl) 2 L n ], [Pt(Thpy)PPh 3 Cl], and [Pt(Thpy)PPh 3 (CH 3 CN)]ClO 4 , crystallographic data and photophysical spectra. S 2 Experimental Section Materials and General Procedures. [Pt(Thpy)(HThpy)Cl] was prepared by literature method. 1 Acetonitrile for photophysical measurements was distilled over potassium permanganate and calcium hydride. Dichloromethane for photophysical studies was washed with concentrated sulfuric acid, 10 % sodium hydrogen carbonate, and water, dried by calcium chloride, and distilled over calcium hydride. All other solvents were of analytical grade and purified according to conventional methods. 2 p-tert-Butylcalix[4]arene was purchased from Alfa Aesar. Instrumentation and Physical Measurements. Fast atom bombardment (FAB) mass spectra were obtained on a Finnigan Mat 95 mass spectrometer with a 3-nitrobenzyl alcohol matrix, whereas electrospray mass spectra were obtained on a LCQ quadrupole ion trap mass spectrometer. High-resolution ESI mass spectra were obtained from a Waters Micromass Q-Tof Premier quadrupole time-of-flight tandem mass spectrometer. 1 H (500 MHz), 13 C (126 MHz) and 31 P (202 MHz) NMR spectra were performed on DPX 500 Bruker FT-NMR spectrometer with chemical shifts (in ppm) relative to tetramethylsilane ( 1 H and 13 C) and H 3 PO 4 ( 31 P) as references. Elemental analyses were performed by the Institute of Chemistry at the Chinese Academy of Sciences, Beijing. UV-vis spectra were recorded on a Perkin Elmer Lambda 19 UV/vis spectrophotometer. Emission and Lifetime Measurements. Steady-state emission spectra were recorded on a Fluorolog-3 Model FL3-21 spectrophotometer. Solution samples for measurements were S 3degassed with at least four freeze-pump-thaw cycles. Low-temperature (77 K) emission spectra for glassy solutions and solid-state samples were recorded in 5 mm diameter quartz tubes, which were placed in a liquid nitrogen Dewar equipped with quartz windows. The emission spectra were corrected for monochromator and photomultiplier efficiency and for xenon lamp stability. Emission lifetime measurements were performed with a Quanta Ray DCR-3 pulsed Nd:YAG laser system (pulse output 355 nm, 8 ns). The emission signals were detected by a Hamamatsu R928 photomultiplier tube and recorded on a Tektronix TDS 350 oscilloscope. Errors for λ values (± 1 nm), τ (± 10 %), Φ (± 10 %) were estimated.Luminescence quantum yields were determined using the method of Demas and Crosby 3 with [Ru(bpy) 3 ]Cl 2 in degassed acetonitrile as a standard reference solution (Φ r = 0.062) and calculated according to the following equation: Φ s = Φ r (B r /B s )(n s /n r ) 2 (D s /D r ), where the subscripts s and r refer to sample and reference standard solution respectively, n is the refractive index of the solvents, D is the integrated intensity, and Φ is the luminescence quantum yield. The quantity B was calculated by B = 1 − 10 −AL , where A is the absorbance at the excitation wavelength and L is the optical path length. . 5,26,27,arene ...

Functionalized oligo(phenylene‐ethynylene)s (OPEs) with different conjugation lengths, p‐X(C6H4C≡C)nSiMe3 (n = 1–4; X = NH2, NMe2, H) were synthesized by Sonogashira coupling of (phenylene‐ethynylene)s and 1‐iodo‐4‐(trimethylsilylethynyl)benzene, followed by desilylation of the p‐substituted (trimethylsilylethynyl)benzenes with potassium hydroxide. The photoluminescent properties for the OPE series with different chain lengths and their solvatochromic responses were examined. The absorption maxima were red‐shifted with increasing numbers of –(C6H4C≡C)– units (n), and a linear plot of the absorption energy maxima vs. 1/n was obtained for each series. The emission spectra in dichloromethane showed a broad and structureless band, the energies of which (in wavenumbers) also fit linearly with 1/n. Both the absorption and emission wavelength maxima of the NH2‐ and NMe2‐substituted OPEs exhibited significant solvent dependence, whereas the parent OPEs (X = H) showed only minor shifts of the λmax values in different solvents. Substituent effects upon the photoluminescent characteristics of the OPEs and the tunability of the excited states were examined with the p‐X(C6H4C≡C)nSiMe3 (n = 2, 3; X = NH2, NMe2, H, SMe, OMe, OH, and F) series. The H‐ and F‐substituted counterparts exhibited high‐energy vibronically structured emissions attributed to the 3(ππ*) excited states of the (arylene‐ethynylene) backbone. For compounds bearing NH2 and NMe2 groups, a broad red‐shifted emission with a remarkable Stokes shift from the respective absorption maximum was observed, which can be assigned to an n → π* transition. The n → π* assignment was supported by MO calculations on the model compounds p‐X(C6H4C≡C)2SiH3 (X = NH2, H). Functionalization of the oligo(arylene‐ethynylene)s with the N‐hydroxysuccinimidyl (NHS) moiety enabled covalent attachment of the fluorophore to HSA protein molecules. A series of fluorescent labels, namely p‐X(C6H4C≡C)nC6H4NHS, (n = 1, X = NH2, NMe2, SMe, OMe, OH, F; n = 2, X = NH2, NMe2) and p‐Me2NC6H4C≡C(C4H2S)C≡CC6H4NHS were synthesized, and their conjugates with HSA (human serum albumin) were characterized by MALDI‐TOF mass spectrometry, UV/Vis absorption spectroscopy, and gel electrophoresis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

A series of cis-dicyanoosmium(II) complexes [Os(PPh3)2(CN)2(N intersectionN)] (N intersectionN = Ph2phen (2a), bpy (2b), phen (2c), Ph2bpy (2d), tBu2bpy (2e)) and [Os(DMSO)2(CN)2(N intersectionN)] (3a-3e, N intersectionN = Br2phen (3f), Clphen (3g)), were synthesized and their spectroscopic and photophysical properties were examined, and [Os(PMe3)2(CN)2(phen)] (4) with axial PMe3 ligands was similarly prepared. The molecular structures of 2a, 2c, [2c.Zn(NO3)2]infinity, 2d, 2e, 3b, 3d, 3e, and 4 were determined by X-ray crystallographic analyses. The two CN ligands are cis to each other with mean Os-C bond distance of 2.0 A. The two PR3 (R = Ph, Me) or DMSO ligands are trans to each other with P/S-Os-P/S angles of approximately 177 degrees . The UV-vis absorption spectra of 2a-2e display an intense absorption band at 268-315 nm (epsilon = approximately (1.54-4.82) x 104 M-1 cm-1) that are attributed to pi --> pi*(N intersection N) and/or pi --> pi*(PPh3) transitions. The moderately intense absorption bands with lambdamax at 387-460 nm (epsilon = approximately (2.4-11.3) x 103 M(-1) cm(-1)) are attributed to a 1MLCT transition. A weak, broad absorption at 487-600 nm (epsilon = approximately 390-1900 M(-1) cm(-1)) is assigned to a 3MLCT transition. Excitation of 2a-2e in dichloromethane at 420 nm gives an emission with peak maximum at 654-703 nm and lifetime of 0.16-0.67 micros. The emission energies, lifetimes, and quantum yields show solvatochromic responses, and plots of numax, tau, and Phi, respectively, versus ET (solvent polarity parameter) show linear correlations, indicating that the emission is sensitive to the local environment. The broad structureless solid-state emission of 2a-2e at 298 (lambdamax 622-707 nm) and 77 (lambdamax 602-675 nm) K are assigned to 3MLCT excited states. The 77 K MeOH/EtOH (1:4) glassy solutions of 2a-2e also exhibit 3MLCT emissions with lambdamax = 560-585 nm. The 1MLCT absorption and 3MLCT emission of 3a-3g occur at lambdamax = 332-390 nm and 553-644 nm, respectively. In the presence of Zn(NO3)2, both the 1MLCT absorption and 3MLCT emission of 2c in acetonitrile blue-shift from 397 to 341 nm and 651 to 531 nm, respectively. The enhancement of emission intensity (I/Io) of 2e at 531 nm reached a maximum of approximately 810 upon the addition of two equivs of Zn(NO3)2. The crystallographic and spectroscopic evidence suggests that 2c undergoes binding of Zn2+ ions via the cyano moieties.