Platinum-Catalyzed Hydrative Dimerization of Alkynylsilanes to α,β-Unsaturated Ketones.

A unique type of platinum catalysis that is valuable for the synthesis of α,β-unsaturated ketones is described. In the presence of PtCl, (2-arylethynyl)trimethylsilanes reacted with HO at 30 °C to give 1,4-diarylbut-3-en-2-ones in moderate to good yields. (2-Alkylethynyl)trimethylsilanes could be efficiently converted into the corresponding hydrative dimerization products by a modified Pt catalyst system.

A case of multiorgan failure due to carbamazepine intoxication successfully treated with multimodal blood purification therapy.

Carbamazepine (CBZ) intoxication can occur due to various factors, including drug interactions and over-ingestion. Extracorporeal elimination, particularly through hemodialysis and hemoperfusion, is effective in treating severe carbamazepine intoxication. However, as the effectiveness of various modalities can differ, method selection may be based on a specific clinical situation.

Palladium-Catalyzed Synthesis of 3,6-Diaryl-1-silylfulvenes: A Promising Entry for Preparing 1,3,6-Triarylfulvenes Bearing Three Different Aryl Groups.

We developed a synthetic methodology for preparing ()-1,3,6-triarylfulvenes bearing three different aryl groups. The reaction of 1,4-diaryl-1-bromo-1,3-butadienes with silylacetylenes in the presence of a palladium catalyst produced ()-3,6-diaryl-1-silyl-fulvenes in good to excellent yields. The (isopropoxy)silylated fulvenes thus obtained were converted to ()-1,3,6-triarylfulvenes bearing different types of aryl substituents.

One-Pot Direct Synthesis of Siloles from 1-Bromo-2-silylethynylbenzenes or 1-Bromo-4-silyl-1,3-enynes.

We propose one-pot synthesis of siloles from readily available starting materials. This methodology is practical for the preparation of multisubstituted siloles in good to excellent yields with complete regioselectivity. Sequential reactions, such as lithiation, silylation, and diisobutylaluminum-hydride-promoted cyclization, enable the preparation of the siloles.

Electrochemical Properties and Electrochromism of 6-Aryl-1,3-bis(trimethylsilyl)fulvenes and Their Derivatives.

In this study, we have disclosed intriguing electrochromic properties of 6-aryl-1,3-bissilylfulvenes. The electrolyte solutions (0.1 M -BuNClO in acetonitrile or dichloromethane) of some 6-aryl-1,3-bissilylfulvenes showed notable color changes when superimposed negative voltages were applied to the solutions.

Synthesis of Polysubstituted Germoles and Benzogermoles Using a Substoichiometric Amount of Diisobutylaluminum Hydride.

We developed a synthetic route to unsymmetrically polysubstituted germoles bearing different substituents from 1-hydrogermyl-4-silyl-1,3-enynes. The reaction proceeded with 0.5 equiv of diisobutylaluminum hydride.

Diisobutylaluminum Hydride Promoted Selectivity-Switchable Synthesis of Benzothiophene Oxides and Benzothiophenes via an Al-Li-Dimetalated Intermediate.

We developed an efficient and direct method for synthesis of benzothiophene oxides from 1-bromo-2-[2-(trimethylsilyl)ethynyl]benzenes and thionyl chloride as an easily accessible source of the sulfinyl group. Benzothiophenes were also synthesized selectively by simply increasing the amount of thionyl chloride. These methods achieved efficient syntheses of various benzothiophene oxides and benzothiophenes.

Palladium-Catalyzed Regio- and Stereoselective Synthesis of ( E)-1,3-Bissilyl-6-arylfulvenes from Aryl Iodides and Silylacetylenes.

An efficient synthetic route to ( E)-1,3-bissilyl-6-arylfulvenes has been developed. The reaction of aryl iodides with trimethylsilylacetylene in the presence of a catalytic amount of PdBr gives 6-aryl-1,3-bis(trimethylsilyl)fulvenes in good to excellent yields with complete regio- and stereoselectivity. The reaction involves trimerization of trimethylsilylacetylene and cleavage of one silyl group.

Diisobutylaluminum Hydride Promoted Cyclization of 1-Hydrosilyl-4-silyl-1,3-enynes to Polysubstituted Siloles.

An efficient method for preparing unsymmetrically multisubstituted siloles is described. The reaction of 1-hydrosilyl-4-silyl-1,3-enynes with diisobutylaluminum hydride (DIBAL-H) gave multisubstituted siloles in good to high yields. This method could be applied to the synthesis of benzosiloles using 2-hydrosilyl-1-(silylethynyl)benzenes as substrates.

Hydroalumination-triggered cyclization of silylated 1,3-dien-5-ynes to polysubstituted benzenes.

Regiocontrolled synthesis of polysubstituted benzenes from silylated 1,3-dien-5-ynes has been achieved by using diisobutylaluminum hydride (DIBAL-H). Hydroalumination of the alkyne moiety with DIBAL-H triggers the aromatic cyclization, which usually proceeds without rearrangement and loss of the existing substituents. The related unusual cyclizations to different types of polysubstituted benzenes are also described.

Diisobutylaluminum hydride promoted cyclization of o-(trimethylsilylethynyl)styrenes to indenes.

The reaction of o-(trimethylsilylethynyl)styrenes with diisobutylaluminum hydride (DIBAL-H) provides 2-trimethylsilyl-1H-indenes efficiently. The cyclization mechanism involves regioselective hydroalumination of the alkynyl moiety, geometrical isomerization of the alkenylaluminums formed, and intramolecular carboalumination. With substrates bearing a 2-(trimethylsilyl)ethenyl group (R(1) = Me3Si, R(2) = R(3) = H), bis-silylated benzofulvenes are obtained upon treatment of the reaction mixture with an excess amount of benzaldehyde.

Platinum-catalyzed one-pot alkenylation of aldehydes using alkynes and triethylsilane: dual catalysis by platinum(II) chloride.

The PtCl2-catalyzed hydrosilylation of terminal alkynes with triethylsilane and subsequent alkenylation of aldehydes with the resultant (E)-alkenylsilanes in a one-pot manner are described. By adding p-benzoquinone and LiI, the latter alkenylation step proceeds smoothly to give allyl silyl ethers in moderate to high yields. This one-pot alkenylation is tolerant to a reasonable range of functional groups.

Nucleophilic addition of α-(dimethylsilyl)nitriles to aldehydes and ketones.

α-Alkylated (dimethylsilyl)acetonitriles (Me2HSiCR(3)R(4)CN) react spontaneously with aldehydes in DMSO to give β-hydroxynitriles in good to high yields. The addition to ketones is effectively promoted by using MgCl2 or CaCl2. (Dimethylsilyl)acetonitrile (Me2HSiCH2CN) shows lower reactivity than the α-alkylated analogues.

Regioselective synthesis of multisubstituted benzenes by palladium-catalyzed intermolecular reaction of β-iodo-β-silylstyrenes with alkynes.

The Pd-catalyzed reaction between β-iodo-β-silylstyrenes and terminal alkynes in i-Pr2NEt gave 1,2,3,5-tetrasubstituted benzenes with complete regioselection. The use of certain silylacetylenes as alkynes enabled efficient synthesis of 1,3,5-trissilyl-2-arylbenzenes, which could be transformed into other multisubstituted benzenes by displacement of the silyl groups.

Dialkylaluminum hydride-promoted cyclodimerization of silylated 1,3-enynes via skeletal rearrangement.

The dialkylaluminum hydride-promoted reaction of 1-silylalk-3-en-1-ynes gave symmetrical 1,2,3,5-tetrasubstituted benzenes as single regioisomers. The novel cyclodimerization via skeletal rearrangement can be rationalized by an unprecedented mechanism involving sequential hydroalumination, alkene isomerization, carboalumination, carbon-carbon bond cleavage, and retro-hydroalumination.

Clinical and cardiac features of patients with subarachnoid haemorrhage presenting with out-of-hospital cardiac arrest.

Background: Subarachnoid haemorrhage (SAH) is known as one of the aetiologies of out-of-hospital cardiac arrest (OHCA). However, the mechanisms of circulatory collapse in these patients have remained unclear.

Methods And Results: We examined 244 consecutive OHCA patients transferred to our emergency department.

[Tricyclic antidepressant overdose rescued by percutanenous cardiopulmonary support: report of two cases].

We report the case of two patients tricyclic antidepressant (TCA) overdoses complicated with severe circulatory failure, successfully resuscitated using percutaneous cardiopulmonary support (PCPS). In case 1, a woman transferred to our emergency department, presented with severe circulatory failure and developed cardiopulmonary arrest. She received prolonged cardiopulmonary resuscitation, and initiated with PCPS.

Prompt prediction of successful defibrillation from 1-s ventricular fibrillation waveform in patients with out-of-hospital sudden cardiac arrest.

Purpose: Ventricular fibrillation (VF) is a common cardiac arrest rhythm that can be terminated by electrical defibrillation. During cardiopulmonary resuscitation, there is a strong need for a prompt and reliable predictor of successful defibrillation because myocardial damage can result from repeated futile defibrillation attempts. Continuous wavelet transform (CWT) provides excellent time and frequency resolution of signals.

Tandem processes identified from reaction screening: nucleophilic addition to aryl N-phosphinylimines employing La(III)-TFAA activation.

Reaction screening of nucleophilic reaction partners for addition to N-diphenylphosphinylimines employing lanthanum(III) triflate as a catalyst and trifluoroacetic anhydride (TFAA) as an activator is reported. A number of tandem processes leading to novel chemotypes including aza-Prins/intramolecular Friedel-Crafts annulations have been identified, and both reaction scope and mechanism further investigated.

Platinum-catalyzed nucleophilic addition of vinylsilanes at the beta-position.

In the presence of catalytic amounts of PtCl(2) and metal iodides, beta-substituted vinylsilanes reacted with aldehydes at the beta-position to give allyl silyl ethers. The Pt-catalyzed addition to aromatic aldehydes proceeded efficiently in the presence of LiI. The combined use of PtCl(2) and MnI(2) was found to be effective in addition to aliphatic aldehydes.

1,2-Migration of phosphorus-centered anions on ate-type copper carbenoids and its application for the synthesis of new potent phosphine ligands.

[chemical reaction: see text]. Diorganophosphide anions, which usually function as nontransferable ligands on mixed cuprates, undergo smooth 1,2-migration on ate-type copper carbenoids. Phosphinodisilylmethylcoppers prepared by this protocol are converted into the corresponding phosphines, which can be used as bulky, highly basic and air-stable ligands.

Diagnostic peritoneal lavage for diagnosing blunt hollow visceral injury: the accuracy of two different criteria and their combination.

Purpose: To test the usefulness of diagnostic peritoneal lavage (DPL) for identifying blunt hollow visceral injury with two different sets of criteria or a combination of the two.

Methods: Fifty victims with physical examinations and/or computed tomography findings equivocal for blunt hollow visceral injury underwent DPL. Whether or not to perform surgery was determined based on Otomo's DPL criteria [lavage white blood cell counts (L-WBC) over lavage red blood cell counts (L-RBC) divided by 150 (L-WBC > or = L-RBC/150) in the presence of hemoperitoneum, or L-WBC over 500/mm(3) (L-WBC > or = 500) in the absence of hemoperitoneum].