Van Houten Kelly A., Heath Danica C., Barringer Chris A., Rheingold Arnold L., Pilato Robert S.
Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, and Department of Chemistry, University of Delaware, Newark, Delaware 19711.
Inorg Chem. 1998 Sep 7;37(18):4647-4653. doi: 10.1021/ic980273j.
The complexes (dppe)M{S(2)C(2)(2-pyridine)(CH(2)CH(2)OC(O)CH(3))} (dppe = 1,2-bis(diphenylphosphino)ethane; M = Pd, Pt) were prepared from 1-(2-pyridyl)-4-acetoxy-2-bromobutan-1-one and the corresponding (dppe)M(SH)(2) complexes. The acetyl group was removed from the metal complexes to yield the corresponding alcohols, (dppe)M{S(2)C(2)(2-pyridine)(CH(2)CH(2)OH)}. The lauroyl derivatives (dppe)M{S(2)C(2)(2-pyridine)(CH(2)CH(2)OC(O)(CH(2))(10)CH(3))} were prepared by esterifying the alcohols with lauroyl chloride. The alkylated pyridinium complexes (dppe)M{S(2)C(2)(CH(2)CH(2)-N-2-pyridinium)} were generated by the addition of either p-toluenesulfonyl chloride or bis(triazole) o-chloroaryl phosphate to (dppe)M{S(2)C(2)(2-pyridine)(CH(2)CH(2)OH)}. [(dppe)Pd{S(2)C(2)(CH(2)CH(2)-N-2-pyridinium)}][BPh(4)] crystallizes in the P&onemacr; space group with a = 9.1924(2) Å, b = 16.0191(2) Å, c = 17.4368(3) Å, alpha = 106.292(2) degrees, beta = 96.235 degrees, and gamma = 95.183(2) degrees. The molecule is best described as a square planar palladium complex with a planar metallo-1,2-enedithiolate which is coplanar with the alkylated pyridinium. The pyridinium-substituted platinum 1,2-enedithiolate complexes have a 1,2-enedithiolate to heterocycle pi charge-transfer transition (ILCT) that is the lowest lying band. Like (dppe)Pt{S(2)C(2)(2-pyridinium)(H)}, (dppe)Pt{S(2)C(2)(CH(2)CH(2)-N-2-pyridinium)} is luminescent in room-temperature solution with two emissive states assigned to the ILCT singlet and triplet. The lifetime of the (1)ILCT is 0.2 ns, (1)phi = 0.002, while the lifetime of the (3)ILCT is 8.3 &mgr;s, (3)phi = 0.01 (DMSO). While (dppe)Pt{S(2)C(2)(CH(2)CH(2)-N-2-pyridinium)} is emissive, the (dppe)Pt{S(2)C(2)(2-pyridinium)(CH(2)CH(2)OR")} complexes are weak emitters at best in solution with triplet quantum yields of <0.0001 (DMSO). These photophysical studies suggest that the heterocycle and the 1,2-enedithiolate must be coplanar in the ILCT excited states for the complexes to be emissive in room-temperature solution.
配合物(dppe)M{S(2)C(2)(2 - 吡啶基)(CH(2)CH(2)OC(O)CH(3))}（dppe = 1,2 - 双（二苯基膦基）乙烷；M = Pd，Pt）由1 - （2 - 吡啶基） - 4 - 乙酰氧基 - 2 - 溴丁烷 - 1 - 酮与相应的(dppe)M(SH)(2)配合物制备而成。从金属配合物中除去乙酰基，得到相应的醇(dppe)M{S(2)C(2)(2 - 吡啶基)(CH(2)CH(2)OH)}。通过用月桂酰氯酯化醇来制备月桂酰衍生物(dppe)M{S(2)C(2)(2 - 吡啶基)(CH(2)CH(2)OC(O)(CH(2))(10)CH(3))}。通过向(dppe)M{S(2)C(2)(2 - 吡啶基)(CH(2)CH(2)OH)}中加入对甲苯磺酰氯或双（三唑）邻氯芳基磷酸酯，生成烷基化吡啶鎓配合物(dppe)M{S(2)C(2)(CH(2)CH(2)-N - 2 - 吡啶鎓)}。[(dppe)Pd{S(2)C(2)(CH(2)CH(2)-N - 2 - 吡啶鎓)}][BPh(4)]在P&onemacr;空间群中结晶，a = 9.1924(2) Å，b = 16.0191(2) Å，c = 17.4368(3) Å，α = 106.292(2)°，β = 96.235°，γ = 95.183(2)°。该分子最好描述为具有平面金属 - 1,2 - 烯二硫醇盐的平面正方形钯配合物，该烯二硫醇盐与烷基化吡啶鎓共面。吡啶鎓取代的铂1,2 - 烯二硫醇盐配合物具有1,2 - 烯二硫醇盐到杂环的π电荷转移跃迁（ILCT），这是最低能级的能带。与(dppe)Pt{S(2)C(2)(2 - 吡啶鎓)(H)}一样，(dppe)Pt{S(2)C(2)(CH(2)CH(2)-N - 2 - 吡啶鎓)}在室温溶液中发光，有两个发射态分别归属于ILCT单重态和三重态。(1)ILCT的寿命为0.2 ns，(1)φ = 0.002，而(3)ILCT的寿命为8.3 μs，(3)φ = 0.01（二甲基亚砜）。虽然(dppe)Pt{S(2)C(2)(CH(2)CH(2)-N - 2 - 吡啶鎓)}发光，但(dppe)Pt{S(2)C(2)(2 - 吡啶鎓)(CH(2)CH(2)OR")}配合物在溶液中充其量是弱发射体，三重态量子产率<0.0001（二甲基亚砜）。这些光物理研究表明，对于配合物在室温溶液中发光，在ILCT激发态下杂环和1,2 - 烯二硫醇盐必须共面。
