Hiroaki Ohno 교수

ADVERTISEMENT RETURN TO ISSUEReviewNEXTSynthesis and Applications of Vinylaziridines and EthynylaziridinesHiroaki Ohno*View Author Information Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan*E-mail [email protected]Cite this: Chem. Rev. 2014, 114, 16, 7784–7814Publication Date (Web):March 31, 2014Publication History Received4 October 2013Published online31 March 2014Published inissue 27 August 2014https://pubs.acs.org/doi/10.1021/cr400543uhttps://doi

Tying up loose ends: A copper(I)-catalyzed three-component reaction has been developed that leads to the formation of 2-(aminomethyl)indole derivatives. Water is the sole theoretical by-product in this reaction in which two CN bonds and one CC bond are formed. This route to the indole nucleus in combination with a palladium-catalyzed functionalization of a CH bond is also useful for the synthesis of polycyclic indoles (see scheme).

Abstract Aniline‐substituted diethynylarenes, which are readily synthesized through Sonogashira coupling reactions from commercially available 1,2‐dihaloarenes, directly produce aryl‐ and heteroaryl‐annulated[ a ]carbazoles by the gold‐catalyzed intramolecular cascade hydroamination/cycloisomerization without producing theoretical by‐products. This new atom‐economical route is easily applicable to various aryl‐annulated[ a ]carbazoles containing an alkyl, aryl or ester substituent.

One-pot N-arylation and oxidative coupling can be promoted by a common palladium catalyst in the presence of appropriate additives: palladium-catalyzed N-arylation of anilines with aryl triflates under the standard conditions followed by addition of acetic acid under oxygen or air atmosphere afforded various types of functionalized carbazoles in good to excellent yields.

We have developed a highly regio- and stereoselective synthesis of medium-sized heterocycles containing one or two heteroatoms via cyclization of bromoallenes bearing an oxygen, nitrogen, or carbon nucleophilic functionality in the presence of a palladium(0) catalyst and alcohol. In this reaction, bromoallenes act as an allyl dication equivalent, and the intramolecular nucleophilic attack takes place exclusively at the central carbon atom of the allene moiety. Interestingly, bromoallenes having

Abstract The development of cascade reactions is an area of considerable interest in modern organic chemistry. Efficient cascade reactions realize the economical synthesis of complex target molecules through multiple bond formations in a single operation. Elementary reactions that form fewer waste products are desirable in terms of atom economy and in order to suppress side product formation in sequential processes. Recent advances in homogeneous gold catalysis have opened up further possibiliti

Indole synthesis by a gold(I)-catalyzed intermolecular formal [4+2] reaction between 1,3-diynes and pyrroles has been developed. This reaction involves the hydroarylation of 1,3-diynes with pyrroles followed by an intramolecular hydroarylation to give the 4,7-disubstituted indoles. This reaction can also be applied to the synthesis of carbazoles when indoles are used as the nucleophiles instead of pyrroles.

Whereas palladium-catalyzed reaction of N-arylsulfonyl-alpha-amino allenes with an aryl iodide (4 equiv) in the presence of potassium carbonate (4 equiv) in DMF at around 70 degrees C affords the corresponding 3-pyrroline derivatives, the reaction in refluxing 1,4-dioxane under otherwise identical conditions yields exclusively or most predominantly the corresponding 2-alkenylaziridines bearing an aryl group on the double bond. Similarly, N-arylsulfonyl-beta-amino allenes can be also cyclized int

In bone metastatic lesions, osteoclasts play a key role in the development of osteolysis. Previous studies have shown that macrophage colony-stimulating factor (M-CSF) is important for the differentiation of osteoclasts. In this study, we investigated whether an inhibitor of M-CSF receptor (c-Fms) suppresses osteoclast-dependent osteolysis in bone metastatic lesions. We developed small molecule inhibitors against ligand-dependent phosphorylation of c-Fms and examined the effects of these compoun

In total and formal syntheses of dictyodendrins B, C, E, and F, the key step involved the direct construction of the pyrrolo[2,3-c]carbazole core by the gold-catalyzed annulation of a conjugated diyne with a pyrrole to form three bonds and two aromatic rings. The subsequent introduction of substituents at the C1 (Suzuki-Miyaura coupling), C2 (addition to an aldehyde), N3 (alkylation), and C5 positions (Ullman coupling) provided divergent access to dictyodendrins.

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFirst Palladium-Catalyzed Aziridination Reaction of Amino AllenesHiroaki Ohno, Ayako Toda, Yoshihisa Miwa, Tooru Taga, Eriko Osawa, Yumiko Yamaoka, Nobutaka Fujii, and Toshiro IbukaView Author Information Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan, and Faculty of Pharmaceutical Sciences, KobeGakuin University, Igawadani-cho, Nishi-ku, Kobe 651-2180, Japan Cite this: J. Org. Chem. 1999, 64, 9, 299

Abstract The development of cascade reactions that realize step‐economical syntheses of complex compounds by multiple bond formation is one of the most attractive subjects in modern organic chemistry. Another important challenge in this area is to improve atom economy by minimizing waste product formation and avoiding prefunctionalization of the substrates. Because palladium catalysts are well known to promote a variety of atom‐economical elementary reactions, many useful palladium‐catalyzed cas

Thermal [2 + 2] cycloaddition of allenes with an additional multiple bond is described. By simply heating the allenenes or allenynes having a three-atom tether in an appropriate solvent such as dioxane or DMF, the distal double bond of the allenic moiety regioselectively participates in the cycloaddition to form bicyclo[4.2.0]oct-5-ene derivatives in good to excellent yields. In all the reactions of allenenes, the olefin geometry was completely transferred to the cycloadducts. While the reaction

Squaring the circle: A route to bicyclo[4.2.0]octane derivatives has been developed by the [2+2] cycloaddition of allenenes or allenynes. The thermal intramolecular [2+2] cycloaddition of simple allenes 1 with an additional multiple bond leads to direct and regioselective formation of the distal adducts 2 in good to excellent yields.

New and interesting polycyclic compounds have been synthesized from non-conjugated diyne systems by dual gold catalysis. A quaternary carbon center in the backbone and the accompanying Thorpe-Ingold effect enabled the unprecedented insertion of sp(3) and sp(2) CH bonds that for the first time were incorporated within the backbone of the diyne system and allowed the construction of complex polycyclic carbon scaffolds inaccessible by previous approaches in which the CH bonds for the insertion we