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The deprotection of the methoxyphenylmethyl (MPM) ether and ester derivatives can be generally achieved by the combinatorial use of a catalytic Lewis acid and stoichiometric nucleophile. The deprotections of 2,4-dimethoxyphenylmethyl (DMPM)-protected alcohols and carboxylic acids were found to be effectively catalyzed by iron(III) chloride without any additional nucleophile to form the deprotected mother alcohols and carboxylic acids in excellent yields. Since the present deprotection proceeds via the self-assembling mechanism of the 2,4-DMPM protective group itself to give the hardly-soluble resorcinarene derivative as a precipitate, the rigorous purification process by silica-gel column chromatography was unnecessary and the sufficiently-pure alcohols and carboxylic acids were easily obtained in satisfactory yields after simple filtration.

The air and water stable title electride is characterized by powder XRD, transport, magnetic, and thermodynamic measurements, PES, and DFT calculations.

This paper reports nitrosoallene-mediated synthesis of α-substituted enoximes. Nucleophilic substitution of nitrosoallenes, a novel chemical species prepared from allenyl N-hydroxysulfonamides, afforded α-functionalized enoximes. Introduction of various nucleophiles proceeded smoothly to form C–N, C–O, C–S, C–F, and C–C bonds in the presence of azodicarboxylates.

3,4-Disubstituted, 3-substituted, and 4-substituted carbazoles, advanced intermediates in the synthesis of natural carbazole alkaloids, are regioselectively synthesized by Diels—Alder reactions of indolines with alkynes.

An efficient method for the synthesis of N-(hetero)arylcarbazoles, useful compounds for functional materials, is reported. Various (hetero)aryl chlorides reacted with N-carbazolylmagnesium chloride in the presence of a palladium catalyst (0.05 to 0.2 mol%) prepared from allylpalladium(II) chloride dimer {[PdCl(allyl)]2} and di-tert-butyl(2,2-diphenyl-1-methylcyclopropan-1-yl)phosphine (cBRIDP) under mild conditions (110 °C) in a short period of time (15 min to 2 h) to give N-(hetero)arylcarbazoles in high yields. The reactions of bromochlorobenzenes proceeded in favour of the bromo group to afford N-(chlorophenyl)carbazoles in a highly selective manner. Functional materials for use in organic light-emitting diodes, such as mCP, 26mcPy, CBP and TCB, were also obtained in high yields within 15 min by the reaction of (hetero)aryl polyhalides. Optimization of the reaction conditions and a postulated catalytic cycle for the reaction are also discussed.

A facile protocol for the direct oxidation of cyclohexanones to phenols using Pd on ZrO2 as catalyst and oxygen as terminal oxidant is developed.

Pd-catalyzed cyclization of substrates (I) provides vinyl indolines, which are further transformed into intermediates of indole alkaloids such as (III) or (IV).

An effective method for the Rh-catalyzed ortho-alkenylation of phenylphosphine sulfides is developed using a P=S group-directed C-H bond cleavage.

A novel and efficient method for the selective monobenzoylation of N-Bz-FTY720 with benzoyl methyl phosphate (BMP) promoted by Zn(OAc)2 and Cs2CO3 was developed. Benzoyl methyl phosphate plays an important role as a biomimetic acylating agent for the monobenzoylation of 1,3-diols.

Intramolecular cyclization of enynes induced by organic seleno radicals has been investigated. Alkaneselenols serve as excellent mediators even under the conditions of fairly high concentration of the substrates, whereas the dilution conditions are essential for the radical cyclization using areneselenols.

Dynamics and mechanisms of infrared multiphoton dissociation of CBrF2CHClF, CBrF2CHBrF, and CBrClFCBrF2 have been studied using a photofragmentation translational spectroscopy. All molecules dissociated through C–Br bond rupture reactions. At high laser fluence, the halogenated ethyl radicals produced by the primary dissociation reactions dissociated through carbon–halogen bond ruptures. Center‐of‐mass product translational energy distributions for the C–Br and C–Cl bond ruptures of all halogenated ethanes and ethyl radicals studied are essentially consistent with those calculated by Rice–Ramsperger–Kassel–Marcus (RRKM) theory. This indicates that there exists essentially no exit channel barrier on the potential energy surface for the C–Br or C–Cl bond rupture of the halogenated ethanes and ethyl radicals.

Three new photochromic lactones closely related to an indolylfulgide were synthesized. While the lactones with the carbonyl group adjacent to the isopropylidene group have large quantum yields of photoreactions, the isomer with the carbonyl adjacent to the indolylethylidene group showed poor photochromic properties. The absorption maxima of the colored forms of the lactones are shorter than that of the indolylfulgide.

An indolylfulgide derivative possessing an orthoester-type functional group on the acid anhydride moiety with a C2-symmetric (S,S)-1,2-bis(1-hydroxypropyl)benzene was prepared. Irradiation of 313-nm light produced the colored form in 90% diastereomer excess. The [α]D values for the colorless and the colored forms in toluene were +82° and −420°, respectively.

[Ca24Al28O64] 4+(e-)4 electride powder with moderate surface area of 9—19 m2/g is synthesized from an 11:14 stoichiometric mixture of Ca(OH)2 and Al(OH)3, which is hydrothermally treated at 150 °C for 5 h.

A highly stereoselective palladium(II)-catalyzed intramolecular cyclization of 1,11-dihydroxyundec-9-en-5-one derivatives via unstable hemiacetal intermediates is reported.

The successful synthesis of novel and well-defined Pd-complexes (PBR and PBD) is developed.

The novel and efficient benzylation method is applicable to a number of anthranilic acids and various alcohols.

Quinoxaline derivatives having bis(fluoromethyl), bis(chloromethyl), or bis(iodomethyl) groups at the 2- and 3-positions, and various electron-donating/withdrawing substituents at the 6- and/or 7-positions, were synthesized. Their antibacterial and antifungal activities were evaluated by means of minimum inhibitory concentration assays. The relationships between the substituents and the antimicrobial activities of the quinoxaline derivatives indicate that the electrophilicity of the halomethyl units plays an important role in generating the antimicrobial activity.

A series of 3-alkylthio- and 3-arylthioindoles is prepared by treatment of indoles with sulfoxides and TFAA followed by dealkylation of resulting sulfonium perchlorates in refluxing dipropylamine.

Pd-catalyzed treatment of o-aminobenzamides with benzyl alcohols provides a new method to prepare various quinazolinones.

The first example of η6-arene ruthenium complexes as chiral templates in the enantioselective title reaction is described.

Palladium-catalyzed S-benzylation of unprotected mercaptobenzoic acids with benzyl alcohols gave only S-benzylated mercaptobenzoic acids in good yields. Water may play an important role for the smooth generation of the (η3-benzyl)palladium species by activation of the hydroxyl group of the benzyl alcohol.

Mo K-edge XAFS measurements on rechargeable molecular cluster batteries in which (NBu4)3[PMo12O40] is used as cathode material and Li metal as anode reveal that all 12 Mo6+ ions in [PMo12O40]3- are reduced to Mo4+ in the discharge process, leading to the formation of [PMo12O40]27-, which stores 24 electrons.

The Co species is an efficient catalyst for the alkoxycarbonylation of epoxides and alcohols and the intra- and intermolecular Pauson—Khand reaction.

Palladium-catalyzed benzylation of unprotected anthranilic acids with benzyl alcohols in the presence of Pd(OAc)2 (5 mol %) and sodium diphenylphosphinobenzene-3-sulfonate (TPPMS, 10 mol %) in water at 120 °C for 16 h gave only dibenzylated anthranilic acids in good yields. Water may play important roles for the smooth generation of the (η3-benzyl)palladium species by activation of the hydroxyl group of the benzyl alcohol.

Pd-catalyzed treatment of anthranilic acids with allylic alcohols in aqueous solution provides a convenient approach to mono-N-allylated anthranilic acids.

A novel method is developed which involves addition of phosphonyl radicals and oxygenation.

Negishi coupling of 3-bromoindole derivatives with zincated iodoaniline provides access to a diversity of chiral tryptophan derivatives (III) in moderate yields.

The catalytic asymmetric Friedel-Crafts/protonation of indoles and pyrroles with α-substituted nitroalkenes to give the corresponding adducts in a highly anti-selective manner was achieved by an imidazoline-aminophenol (L2)-Cu complex. The anti-adducts could be successfully transformed to biochemically important α-substituted β-heteroarylalkylamines.

An ionic liquid with Lewis acid sites in anion and cation is synthesized and shown to be an effective catalyst for the conversion of aliphatic and aromatic aldoximes (I) into the corresponding nitriles (II).

A four-step synthetic route to fully substituted chiral tetrahydro-β-carbolines (THBCs) is described. Starting from the (R,S,S)-Friedel-Crafts/Henry adduct obtained from three-component coupling of an indole, nitroalkene, and aldehyde catalyzed by imidazoline-aminophenol-CuOTf, the (1S,3S,4R)-THBCs were readily synthesized in a three-step operation including reduction of the nitro-functionality and Pictet-Spengler cyclization.

(NBu4)3[PMo12O40] molecules are grafted onto the surface of single-wall carbon nanotubes by addition of a MeCN solution of the polyoxometalate to a toluene suspension of the nanotubes under vigorous stirring at room temperature.

Starting from tribromopyridine, the title compounds are prepared by regioselective amination yielding dibromopyridines (I), followed by successive coupling.

Stomatin is a major integral membrane protein of human erythrocytes, the absence of which is associated with a form of hemolytic anemia known as hereditary stomatocytosis. It is reported that stomatin regulates the gating of acid-sensing ion channels in mammalian neurons. However, the function of stomatin is not fully understood. In the genomic sequence of the hyperthermophilic archaeon Pyrococcus horikoshii, the putative operon-forming genes PH1511 and PH1510 encode stomatin and its partner protein, respectively. The N-terminal region of PH1510p (1510-N) is a serine protease, and specifically cleaves the C-terminal hydrophobic region of stomatin PH1511p. We have determined the first crystal structure of the core domain of stomatin PH1511p (residues 56-234, designated as PhSto(CD)). This review focuses on the three-dimensional structure of PhSto(CD), and discusses the function of stomatin and its specific protease 1510-N. PhSto(CD) forms a novel homotrimeric structure. Three α/β domains form a triangle of about 50 A on each side, and three α-helical segments about 60 A in length extend from the apexes of the triangle. The α/β domain of PhSto(CD) is partly similar in structure to the band-7 domain of mouse flotillin-2. While the α/β domain is relatively rigid, the α-helical segment shows a conformational flexibility, adapting to the neighboring environment. One α-helical segment forms an anti-parallel coiled-coil with another α-helical segment from a symmetry-related molecule. The α-helical segment shows a heptad repeat pattern, and mainly hydrophobic residues form a coiled-coil interface. The coiled-coil fold observed in the crystal probably contributes to the self-association.

The total synthesis of 2-deoxy-D-ribose (VIII) is achieved in 12 steps from L-(-)malic acid (I) via an unstable hemiacetal.