- Synthesis of (Z)-β-(Carbonylamino)alkenylindium through Regioselective anti-Carboindation of Ynamides and Its Transformation to Multisubstituted Enamides
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The regioselective anti-carboindation of ynamides by using InBr3 and silylated nucleophiles was developed to synthesize (Z)-β-(carbonylamino)alkenylindiums. The X-ray crystallographic analysis of an alkenylindium suggested that the reaction proceeded in an anti-addition fashion. In contrast to reported syn-carbometalations of ynamides by using organometallics, a cooperation of InBr3 and silylated nucleophiles to ynamides achieved an anti-addition, which was supported by DFT calculations. The scope of substrates included various ynamides and silylated nucleophiles, such as silyl ketene acetals and silyl ketene imines. The transformation of synthesized alkenylindiums by iodination, radical coupling, and Pd-catalyzed cross-coupling successfully afforded trisubstituted enamines with high regio- and stereoselectivities.
- Kang, Kyoungmin,Sakamoto, Kosuke,Nishimoto, Yoshihiro,Yasuda, Makoto
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- Decarboxylative Ritter-Type Amination by Cooperative Iodine (I/III)─Boron Lewis Acid Catalysis
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Recent years have witnessed important progress in synthetic strategies exploiting the reactivity of carbocations via photochemical or electrochemical methods. Yet, most of the developed methods are limited in their scope to certain stabilized positions in molecules. Herein, we report a metal-free system based on the iodine (I/III) catalytic manifold, which gives access to carbenium ion intermediates also on electronically disfavored benzylic positions. The unusually high reactivity of the system stems from a complexation of iodine (III) intermediates with BF3. The synthetic utility of our decarboxylative Ritter-type amination protocol has been demonstrated by the functionalization of benzylic as well as aliphatic carboxylic acids, including late-stage modification of different pharmaceutical molecules. Notably, the amination of ketoprofen was performed on a gram scale. Detailed mechanistic investigations by kinetic analysis and control experiments suggest two mechanistic pathways.
- Narobe, Rok,Murugesan, Kathiravan,Schmid, Simon,K?nig, Burkhard
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p. 809 - 817
(2022/01/15)
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- Acetonitrile and benzonitrile as versatile amino sources in copper-catalyzed mild electrochemical C-H amidation reactions
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A mild, efficient electrochemical approach to the site-selective direct C-H amidation of benzene and its derivatives with acetonitrile and benzonitrile has been developed. It has been shown that joint electrochemical oxidation of various arenes in the presence of a copper salt as a catalyst and nitriles leads to the formation of N-phenylacetamide from benzene and N-benzylacetamides from benzyl derivatives (up to 78% yield). A favorable feature of the process is mild conditions (room temperature, ambient pressure, no strong oxidants) that meet the criteria of green chemistry.
- Budnikova, Yulia,Kononov, Alexander,Rizvanov, Ildar,Strekalova, Sofia
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p. 37540 - 37543
(2021/12/07)
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- C-H Amination via Electrophotocatalytic Ritter-Type Reaction
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A method for C-H bond amination via an electrophotocatalytic Ritter-Type reaction is described. The reaction is catalyzed by a trisaminocyclopropenium (TAC) ion in an electrochemical cell under irradiation. These conditions convert benzylic C-H bonds to acetamides without the use of a stoichiometric chemical oxidant. A range of functionality is shown to be compatible with this transformation, and several complex substrates are demonstrated.
- Lambert, Tristan H.,Shen, Tao
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supporting information
p. 8597 - 8602
(2021/06/28)
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- Formation of indoles, dihydroisoquinolines, and dihydroquinolines by ruthenium-catalyzed heterocyclizations
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Indoles, dihydroisoquinolines, and dihydroquinolines were efficiently prepared by ruthenium-catalyzed heterocyclizations of aromatic homo- and bis-homopropargyl amines/amides in the presence of an amine/ammonium base-acid pair. These regioselective 5-endo and 6-endo cyclizations most probably occur by nucleophilic trapping of key ruthenium-vinylidene intermediates. Georg Thieme Verlag Stuttgart · New York.
- Varela-Fernández, Alejandro,Varela, Jesús A.,Saá, Carlos
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p. 3285 - 3295
(2013/01/15)
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- Intramolecular cyclization of ortho-alkynylanilines by Rh(I)-catalyzed hydroamination to yield benzo(dipyrroles)
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The methylene-bridged Rh(I) dicarbonyl complex, [Rh(bim) (CO)2+ BPh4-] (1) (bim = bis(N-methylimidazol-2-yl)methane), is an effective catalyst for the intramolecular hydroamination of selected ortho-alkynylanilines to give a range of benzo(dipyrroles).
- Clentsmith, Guy K.B.,Field, Leslie D.,Messerle, Barbara A.,Shasha, Adelle,Turner, Peter
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supporting information; experimental part
p. 1469 - 1471
(2009/06/08)
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- RENIN INHIBITORS
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The present invention relates to biphenyl compounds of formula (I). These compounds are renin inhibitors of a non- peptidic nature and of low molecular weight. The invention further relates to a pharmaceutical composition containing said compounds, as wel
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Page/Page column 29
(2009/04/25)
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- Chemistry of unprotected amino acids in aqueous solution: Direct bromination of aromatic amino acids with bromoisocyanuric acid sodium salt under strong acidic condition
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Brominations of unprotected aromatic amino acids such as phenylalanine, tyrosine, and glycine, with bromoisocyanuric acid mono sodium salt (BICA-Na) were conducted in 60% aq. H2SO4 at 0°C to give a mixture of mono-brominated products in good yield. Unexpectedly, meta-bromophenylglycine was obtained as main product accompanied by ortho- and para-substituted products, while phenylalanine gave only ortho- and para-substituted products. Bromination of 2-phenylethylamine or benzylamine showed a tendency similar to the corresponding amino acids.
- Yokoyama, Yuusaku,Yamaguchi, Tomotsugu,Sato, Masanori,Kobayashi, Eri,Murakami, Yasuoki,Okuno, Hiroaki
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p. 1715 - 1719
(2007/10/03)
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