Takashi Nakamoto
Kitasato University
Proton NMRAdductChemical shiftHydrogen bondResonance (chemistry)Natural bond orbitalPlanarMolecular orbitalChalcogenPlane (geometry)Ab initio quantum chemistry methodsChemistryConformational isomerismDynamic stereochemistryX-rayCenter (category theory)QuinoneInterpretation (model theory)Group (periodic table)Anthraquinone DerivativesStructural dependenceChemical solution1h nmr spectroscopyMoleculeAlpha effectMolecular physicsHalogenSpectral lineX-ray crystallographyAtoms in moleculesGround stateStereochemistryCrystallographyTransition stateActivation energyHypervalent molecule
Publications 5
#1Satoko Hayashi (Wakayama University)H-Index: 25
#2Takashi NakamotoH-Index: 3
Last. Waro NakanishiH-Index: 25
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The p(Z)−π(Ar) conjugations must operate fully in the ground states of 9-(arylchalcogenyl)triptycenes (p-YC6H4ZTpc:1 (Z = O), 2 (Z = S), 3 (Z = Se), and 4 (Z = Te)), where the p-YC6H4 group is placed in the bisected area between two phenyl planes of the triptycyl group with the parallel orientation. The ground-state geometries, which we call (A: pl), are confirmed by X-ray analysis. However, the conjugations never operate in the transition states between (A: pl) and/or the topomeric structures (...
9 CitationsSource
#1Takashi Nakamoto (Wakayama University)H-Index: 3
#2Satoko Hayashi (Wakayama University)H-Index: 25
Last. Gaku Yamamoto (Kitasato University)H-Index: 1
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9-(Arylselanyl)triptycenes (1: p-YC6H4SeTpc) should supply the planar structure (pl) around the p-YC6H4Se (ArSe) group in the ground state, irrespective of the p-Y substituents. 1 with Y = H (a), NMe2 (b), OMe (c), Cl (d), CN (e) and NO2 (f) are prepared. Structures of 1a–d and 1f are determined by X-ray analysis and dynamic 1H NMR spectroscopy is applied to 1a, 1c, 1e and 1f. For convenience of discussion, the structure of 1 is defined as follows: a conformer around the triptycyl group in 1 is ...
1 CitationsSource
#1Takashi Nakamoto (Wakayama University)H-Index: 3
#2Satoko HayashiH-Index: 25
Last. Waro NakanishiH-Index: 25
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A set of new δ(Se) parameters is proposed as a standard for the planar (pl) orientational effect of p-YC6H4 (Ar) in ArSeR, employing 9-(arylselanyl)triptycenes (1: p-YC6H4SeTpc). The Se−CR bond in ArSeR is placed on the Ar plane in pl and it is perpendicular to the plane in pd. Large upfield shifts are observed for Y = NMe2, OMe, and Me (−22 to −6 ppm) and large downfield shifts for Y = COOEt, CN, and NO2 (19−37 ppm), relative to Y = H, with small upfield and moderate downfield shifts by Y of ha...
10 CitationsSource
#1Waro Nakanishi (Wakayama University)H-Index: 25
#2Takashi Nakamoto (Wakayama University)H-Index: 3
Last. Norihiro Tokitoh (Kyoto University)H-Index: 62
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To clarify the nature of five-center, six-electron (5c-6e) C 2 Z 2 O interactions, atoms-in-molecules (AIM) analysis has been applied to an anthraquinone, 1,8-(MeZ) 2 ATQ (1 (Z=Se), 2 (Z=S), and 3 (Z=O)), and a 9-methoxyanthracene system, 9-MeO-1,8-(MeZ) 2 ATC (4 (Z=Se), 5 (Z=S), and 6 (Z=O)), as well as 1-(MeZ)ATQ (7 (Z=Se), 8 (Z=S), and 9 (Z=O)) and 9-MeO-1-(MeZ)ATC (10 (Z=Se), 11 (Z=S), and 12 (Z=O)). The total electronic energy density (H b (r c )) at the bond critical points (BCPs), an appr...
73 CitationsSource
#1Waro NakanishiH-Index: 25
#2Satoko HayashiH-Index: 1
Last. Masahiko HadaH-Index: 33
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