[{Ni(dmpe)}(2)(μ-SiHPh(2))(2)] (dmpe = 1,2-bis(dimethylphosphino)ethane) reacted with PhC≡CPh to yield fluorescent 1,2-bis{(E)-1,2-diphenylethenyl}-1,1,2,2-tetraphenyldisilane via addition of the Si-H bond of the ligand to the alkyne and subsequent coupling of the tertiary silyl ligands forming the Si-Si bond.

A dinickel complex with bridging silyl ligands, [{Ni(PCy3)}2(μ-SiHPh2)2] (1), prepared from [Ni(cod)2], PCy3, and H2SiPh2, underwent exchange of the PCy3 ligands with 1,2-bis(dimethylphosphino)ethane (dmpe) to yield a complex coordinated by the two bidentate ligands, [{Ni(dmpe)}2(μ-SiHPh2)2]. Reactions of diarylacetylenes, ArCCAr (Ar = C6H5, C6H4OMe-4, C6H4Me-4, C6H4F-4, C6H4CF3-4, C6H4CN-4), with 1 in a 4/1 ratio afforded 1,2-bis{(E)-1,2-diarylethenyl}-1,1,2,2-tetraphenyldisilanes via addition of the Si–H bond of the bridging silyl ligand to the alkynes and subsequent coupling of the resulted tertiary silyl ligand. X-ray crystallography of the dialkenyldisilanes resulted in three kinds of conformation of the CC–Si–Si–CC chain depending on the aryl group at the vinyl carbon. The disilane with phenyl substituents, 4a (Ar = C6H5), contained a planar CC–Si–Si–CC alignment with small Si–Si–CC torsion angles (1.7(5) and 6.9(5)°). The other dialkenyldisilanes, 4b,c,e,f, had much larger torsion angles (30.9(3)–49.2(3)°), and the twisted conformation of the molecules was classified into two types. Compound 4a exhibited a fluorescence maximum at 488 nm in the solid state, while 4b–f showed peaks at 393–427 nm. The red shift in the emission of 4a is ascribed to orthogonal intramolecular charge transfer (OICT) from the electron-donating Si–Si to accepting CC bonds.

A heterobimetallic PtPd complex supported by three bridging diphenylsilylene ligands, [Pt{Pd(dmpe)} (μ -SiPh ) ] (1, dmpe=1,2-bis(dimethylphosphino)ethane), has been synthesized from mononuclear Pd and Pt complexes. The hexagonal core composed of Pt, Pd, and Si atoms is slightly larger than that of the tetrapalladium complex, [Pd{Pd(dmpe)} (μ -SiPh ) ] (2). Reaction of PhSiH with complex 1 in the presence and absence of Ph SiH results in the formation of a tetranuclear complex with silyl and hydride ligands at the Pt center, [PtH(SiPh H){Pd(dmpe)} (μ -SiHPh) ] (3), and an octanuclear complex, [{Pt{Pd(dmpe)} (μ -SiHPh) } (κ -dmpe)] (5), respectively. Both M-Si (M=Pt, Pd) bond lengths and the Si NMR chemical shifts of 1 and 2 are located between those of mononuclear late transition-metal complexes with a silylene ligand and complexes with donor-stabilized silylene ligands. CuI and AgI adducts of 1 and 2, formulated as [M(μ-M'I){Pd(dmpe)} (μ -SiPh ) ] (M=Pt, Pd; M'=Cu, Ag), undergo elimination of CuI (AgI) and regenerate the tetrametallic complexes upon heating or addition of a chelating diphosphine. Elimination of AgI from 2-AgI occurs more rapidly than elimination of CuI from 2-CuI, as determined from the results of kinetics experiments.

Introduction: Hypothermic out-of-hospital cardiac arrest (OHCA) is assumed to be associated with favorable neurological outcomes compared with OHCA from other etiologies. However, supporting evidence is limited. In addition, inconsistencies for number of defibrillation and adrenaline administration attempts in prehospital management guidelines can be identified. Hypothesis: We evaluated whether hypothermic OHCA is associated with favorable outcomes compared with OHCA from other etiologies. Further, the effectiveness of defibrillation or adrenaline administration was evaluated. Methods: Using data from a nationwide, population-based retrospective study conducted in Japan from 2013 to 2016, we compared two OHCA patient groups: patients with hypothermic etiology and those with non-hypothermic etiology. The primary outcome measure was one-month favorable neurological outcomes, defined as Cerebral Performance Category score ≤ 2. Multivariable logistic regression was used to calculate odds ratios (ORs) and their confidence intervals (CIs) to evaluate the impact of hypothermic OHCA. We further looked for an association between prehospital management and neurological outcomes among patients with hypothermic etiology. Results: We divided the cohort of 477,606 OHCA patients into the hypothermic group (n=842) and the non-hypothermic group (n=476,763). The hypothermic group had significantly higher odds of favorable neurological outcomes (64/842 (7.6%) vs. 13,052/476,763 (1.4 %), adjusted OR 3.12, 95%, CI 1.96-4.96) compared with the non-hypothermic group. In the hypothermic group, prehospital defibrillation (OR 1.52, 95%, CI 0.86-2.68) and adrenaline administration (OR 1.32, 95%, CI 0.67-2.62) did not contribute to favorable neurological outcomes overall. However, when the data was stratified by age and number of shocks, three or less defibrillation attempts in patients under 65 years old (OR 3.37, 95%, CI 1.31-8.67) was associated with favorable neurological outcomes. Conclusion: We found that hypothermic OHCA was associated with a higher chance of a favorable neurological outcome. Even prehospital defibrillation seems to have limited efficacy for hypothermic OHCA.