- Tunable Ligand Effects on Ruthenium Catalyst Activity for Selectively Preparing Imines or Amides by Dehydrogenative Coupling Reactions of Alcohols and Amines
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Selective dehydrogenative synthesis of imines from a variety of alcohols and amines was developed by using the ruthenium complex [RuCl2(dppea)2] (6 a: dppea=2-diphenylphosphino-ethylamine) in the presence of catalytic amounts of Zn(OCOCF3)2 and KOtBu, whereas the selective dehydrogenative formation of amides from the same sources was achieved by using another ruthenium complex, [RuCl2{(S)-dppmp}2] [6 d: (S)-dppmp=(S)-2-((diphenylphosphenyl)methyl)pyrrolidine], in the presence of catalytic amounts of Zn(OCOCF3)2 and potassium bis(trimethylsilyl)amide (KHMDS). Our previously reported ruthenium complex, [Ru(OCOCF3)2(dppea)2] (8 a), was the catalyst precursor for the imine synthesis, whereas [Ru(OCOCF3)2{(S)-dppmp}2] (8 d), which was derived from the treatment of 6 d with Zn(OCOCF3)2 and characterized by single-crystal X-ray analysis, was the pre-catalyst for the amide formation. Control experiments revealed that the zinc salt functioned as a reagent for replacing chloride anions with trifluoroacetate anions. Plausible mechanisms for both selective dehydrogenative coupling reactions are proposed based on a time-course study, Hammett plot, and deuterium-labeling experiments.
- Higuchi, Takafumi,Tagawa, Risa,Iimuro, Atsuhiro,Akiyama, Shoko,Nagae, Haruki,Mashima, Kazushi
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p. 12795 - 12804
(2017/09/06)
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- Intramolecular C(sp3)-N coupling by oxidation of benzylic C,N-dianions
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What a couple! An intramolecular, C(sp3)-N coupling to afford azacycles is reported. This reaction proceeds through the oxidation of benzylic C,N-dianions with iodine and builds on an earlier discovery during the synthesis of the natural produc
- Jeffrey, Jenna L.,Bartlett, Emily S.,Sarpong, Richmond
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supporting information
p. 2194 - 2197
(2013/03/28)
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- AMIDE RESORCINOL COMPOUNDS
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The present invention is directed to compounds of formula (I), and pharmaceutically acceptable salts and solvates thereof, their synthesis, and their use as HSP-90 inhibitors.
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Page/Page column 35-36; 98
(2008/06/13)
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- An Evaluation of Amide Group Planarity in 7-Azabicyclo[2.2.1]heptane Amides. Low Amide Bond Rotation Barrier in Solution
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Here we show that amides of bicyclic 7-azabicyclo[2.2.1]heptane are intrinsically nitrogen-pyramidal. Single-crystal X-ray diffraction structures of some relevant bicyclic amides, including the prototype N-benzoyl-7-azabicyclo[2.2.1]heptane, exhibited nitrogen-pyramidalization in the solid state. We evaluated the rotational barriers about the amide bonds of various N-benzoyl-7-azabicyclo[2.2.1]heptanes in solution. The observed reduction of the rotational barriers of the bicyclic amides, as compared with those of the monocyclic pyrrolidine amides, is consistent with a nitrogen-pyramidal structure of 7-azabicyclo[2.2.1]heptane amides in solution. A good correlation was found between the magnitudes of the rotational barrier of N-benzoyl-7-azabicyclo[2.2.1]heptanes bearing para-substituents on the benzoyl group and the Hammett's σp+ constants, and this is consistent with the similarity of the solution structures. Calculations with the density functional theory reproduced the nitrogen-pyramidal structures of these bicyclic amides as energy minima. The calculated magnitudes of electron delocalization from the nitrogen nonbonding nN orbital to the carbonyl π* orbital of the amide group evaluated by application of the bond model theory correlated well with the rotational barriers of a variety of amides, including amides of 7-azabicyclo[2.2.1]heptane. The nonplanarity of the amide nitrogen of 7-azabicyclo[2.2.1]heptanes would be derived from nitrogen-pyramidalization due to the CNC angle strain and twisting of the amide bond due to the allylic strain.
- Otani, Yuko,Nagae, Osamu,Naruse, Yuji,Inagaki, Satoshi,Ohno, Masashi,Yamaguchi, Kentaro,Yamamoto, Gaku,Uchiyama, Masanobu,Ohwada, Tomohiko
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p. 15191 - 15199
(2007/10/03)
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- A NEW SYNTHESIS OF AMIDES FROM ACYL FLUORIDES AND N-SILYLAMINES
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Amide bonds are formed readily under mild conditions by the reaction of N-silylamines with the hydrolytically stable acyl fluorides.
- Rajeswari, Sundaramoorthi,Jones, Robert J.,Cava, Michael P.
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p. 5099 - 5102
(2007/10/02)
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