Copper-Catalyzed Single C-H Amination of 8-Aminoquinoline-Directed Ferrocenes.

An unprecedented copper-catalyzed C-H monoamination of ferrocenes directed by an 8-aminoquinoline amide directing group is described. This reaction proceeds in the presence of a catalytic amount of copper catalyst with both cyclic and acyclic amines to afford the various aminoferrocenes. The C-H amination of ortho-substituted ferroceneamides was also achieved, enabling rapid access to multisubstituted ferrocenes that are useful for developing new functional molecules.

Delayed Obstructive Hydrocephalus After Cardiac Surgery With Cardiopulmonary Bypass in a Patient With Cerebellar Infarction: A Case Report.

Obstructive hydrocephalus caused by brainstem compression is a life-threatening complication and usually occurs within 6 days, with peak on day 3 after onset of cerebellar infarction. We present a case of obstructive hydrocephalus that developed on day 8 in a patient with cerebellar infarction. A 39-year-old man with cerebellar infarction caused by myocardial infarction-related intraventricular thrombus underwent left ventricular thrombectomy under cardiopulmonary bypass. He was lucid postoperatively, but his consciousness was diminished on day 8 because of obstructive hydrocephalus. Cerebral edema due to cardiopulmonary bypass may contribute to delayed onset of obstructive hydrocephalus, especially in patients with large-sized cerebellar infarction.

Control of photobleaching in photodynamic therapy using the photodecarbonylation reaction of ruthenium phthalocyanine complexes via stepwise two-photon excitation.

In this study, we have investigated the photochemical properties and photodynamic effects of ruthenium phthalocyanine (RuPc(CO)(Py)) and naphthalocyanine (RuNc(CO)(Py)) complexes. When a nanosecond-pulsed laser is used, the photodecarbonylation of our Ru complexes efficiently proceeds via stepwise two-photon excitation, while the reaction yields are negligibly small when a continuous-wave (CW) laser is employed. The pulsed laser selective photodecarbonylation decreases the Q-band absorbance, which satisfies what the photodynamic therapy (PDT) requires of the photobleaching. For RuPc(CO)(Py), the photochemical reactions including both the photodecarbonylation and just photobleaching occur in HeLa cells in vitro. Toxicity and phototoxicity tests indicate that our RuPc(CO)(Py) and RuNc(CO)(Py) complexes in concentrations of 0.3-1 microM and 1-2 microM, respectively, are applicable as PDT agents. The phototoxicity is consistent with the photochemical properties of these complexes, namely, excited triplet lifetimes (10 and 4.8 micros for the Pc and Nc complexes, respectively) and singlet oxygen yields (0.48 and 0.35 for the Pc and Nc complexes, respectively). On the basis of these results, we propose a novel concept for achieving a greater depth of necrosis in PDT as follows: (1) PDT of upper cellular layers using CW-laser irradiation; (2) efficient photobleaching in upper cellular layers using pulsed dye-laser irradiation, which results in an increase in the therapeutic depth of red light; (3) PDT directed toward deeper tumor tissues using CW laser irradiation. In addition, these Ru complexes are promising as CO release agents for investigative biochemistry.

Chiral triazolylidene-Pd-PEPPSI: synthesis, characterization, and application in asymmetric Suzuki-Miyaura cross-coupling.

A chiral triazolylidene-Pd-PEPPSI (PEPPSI = pyridine, enhanced, precatalyst, preparation, stabilization, initiation) complex with ferrocene-based planar chirality has been synthesized and characterized. Investigation of the electronic and steric nature of this complex revealed its powerful electron-donating ability (TEP 2044 cm-1) and high steric bulk (%Vbur = 42.2). These unique properties allow the complex to exhibit very high catalytic activity (TON = 420) for asymmetric Suzuki-Miyaura cross-coupling, providing the coupling product with good enantioselectivity (75% ee).

Bulky iodotriazolium tetrafluoroborates as highly active halogen-bonding-donor catalysts.

Steric bulk around catalytic centers is one of the most important factors determining catalytic reactivities and selectivities. This paper reports the synthesis of structurally diverse 5-iodo-3-methyl-1,2,3-triazolium salts and the evaluation of their catalytic activities as halogen-bonding donors for the aza-Diels-Alder reaction of 2-siloxy-1,3-butadiene with imines. We found that steric hindrance around an iodide atom in halogen-bonding donors significantly impacted catalytic efficiency.

Photodecarbonylation of ruthenium carbonyl octaethylporphyrin via stepwise two-photon absorption of visible light.

The photoinduced decarbonylation of a ruthenium(II) carbonyl octaethylporphyrin (RuOEP(CO)(Py)) complex has been shown to occur upon nanosecond pulse laser irradiation as a visible light excitation source, which is reasonably interpreted by a stepwise two-photon absorption process.