Lewis Base Mediated β-Elimination and Lewis Acid Mediated Insertion Reactions of Disilazido Zirconium Compounds

2013 ◽  
Vol 135 (40) ◽  
pp. 15225-15237 ◽  
Author(s):  
KaKing Yan ◽  
Juan J. Duchimaza Heredia ◽  
Arkady Ellern ◽  
Mark S. Gordon ◽  
Aaron D. Sadow
Keyword(s):  
Lewis Acid ◽  
Lewis Base ◽  
Insertion Reactions ◽  
Zirconium Compounds

The structure and activity of potassium supported on SBA-15 molecular sieve: Density functional theory study

2014 ◽  
Vol 13 (01) ◽  
pp. 1350076 ◽  
Author(s):  
Bing Liu ◽  
Daxi Wang ◽  
Zhongxue Wang ◽  
Zhen Zhao ◽  
Yu Chen ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Lewis Acid ◽  
Molecular Sieve ◽  
Active Sites ◽  
Density Functional ◽  
Structural Model ◽  
Vibrational Frequencies ◽  
Oxygen Molecule ◽  
Lewis Base ◽  
Functional Theory

The geometries, vibrational frequencies, electronic properties and reactivity of potassium supported on SBA-15 have been theoretically investigated by the density functional theory (DFT) method. The structural model of the potassium supported on SBA-15 was constructed based on our previous work [Wang ZX, Wang DX, Zhao Z, Chen Y, Lan J, A DFT study of the structural units in SBA-15 mesoporous molecular sieve, Comput. Theor. Chem.963, 403, 2011]. This paper is the extension of our previous work. The most favored location of potassium atom was obtained by the calculation of substitution energy. The calculated vibrational frequencies of K /SBA-15 are in good agreement with the experimental results. By analyzing the properties of electronic structure, we found that the O atom of Si - O (2)- K group acts as the Lewis base center and the K atom acts as the Lewis acid center. The reactivity of K /SBA-15 was investigated by calculating the activation of oxygen molecule. The oxygen molecule can be activated by K /SBA-15 with an energy barrier of 103.2 kJ/mol. In the final state, the activated oxygen atoms become new Lewis acid centers, which are predicted to act as the active sites in the catalytic reactions. This study provides a deep insight into the properties of supported potassium catalysts and offers fundamental information for further research.

Erratum to “Synthesis and structure of potential Lewis acid–Lewis base bifunctional catalysts: 2-N,N-diisopropylaminobenzylboronate derivatives” [J. Organomet. Chem. 690 (2005) 4784–4793]

2006 ◽  
Vol 691 (3) ◽  
pp. 538
Author(s):  
Samuel W. Coghlan ◽  
Richard L. Giles ◽  
Judith A.K. Howard ◽  
Leonard G.F. Patrick ◽  
Michael R. Probert ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Lewis Base ◽  
Bifunctional Catalysts

scholarly journals Lewis acid- and/or Lewis base-catalyzed [3+2] cycloaddition reaction: synthesis of pyrazoles and pyrazolines

2008 ◽  
Vol 49 (48) ◽  
pp. 6768-6772 ◽  
Author(s):  
Palakodety Radha Krishna ◽  
Empati Raja Sekhar ◽  
Florence Mongin
Keyword(s):  
Lewis Acid ◽  
Cycloaddition Reaction ◽  
Lewis Base ◽  
Reaction Synthesis

Empirical Lewis acid strengths for 135 cations bonded to oxygen

2017 ◽  
Vol 73 (5) ◽  
pp. 956-961 ◽  
Author(s):  
Olivier Charles Gagné ◽  
Frank Christopher Hawthorne
Keyword(s):  
Lewis Acid ◽  
Strong Correlation ◽  
Ionization Energy ◽  
Acid Strength ◽  
Lewis Base

New and updated Lewis acid strengths are listed for 135 cations bonded to oxygen for use with published Lewis base strengths. A strong correlation between Lewis acid strength and ionization energy is shown, and correlation with electronegativity is confirmed.

scholarly journals Lewis Base Activation of Lewis Acid: A Detailed Bond Analysis

ACS Omega ◽  
2018 ◽  
Vol 3 (11) ◽  
pp. 16292-16300 ◽  
Author(s):  
Gianluca Ciancaleoni
Keyword(s):  
Lewis Acid ◽  
Lewis Base

scholarly journals π-Hole Tetrel Bonds—Lewis Acid Properties of Metallylenes

Crystals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 112
Author(s):  
Sławomir J. Grabowski
Keyword(s):  
Quantum Theory ◽  
Crystal Structures ◽  
Lewis Acid ◽  
Natural Bond Orbital ◽  
Database Search ◽  
Lewis Base ◽  
Atoms In Molecules ◽  
Acid Properties ◽  
Structural Database ◽  
Tetrel Bonds

The MP2/aug-cc-pVTZ calculations were performed on the dihalometallylenes to indicate their Lewis acid and Lewis base sites. The results of the Cambridge Structural Database search show corresponding and related crystal structures where the tetrel center often possesses the configuration of a trigonal bipyramid or octahedron. The calculations were also carried out on dimers of dichlorogermylene and dibromogermylene and on complexes of these germylenes with one and two 1,4-dioxide molecules. The Ge⋯Cl, Ge⋯Br, and Ge⋯O interactions are analyzed. The Ge⋯O interactions in the above mentioned germylene complexes may be classified as the π-hole tetrel bonds. The MP2 calculations are supported by the results of the Quantum Theory of Atoms in Molecules (QTAIM) and the Natural Bond Orbital (NBO) approaches.

Recent progress in Lewis acid-Lewis base bifunctional asymmetric catalysis

2005 ◽  
Vol 77 (12) ◽  
pp. 2047-2052 ◽  
Author(s):  
Motomu Kanai ◽  
Nobuki Kato ◽  
Eiko Ichikawa ◽  
Masakatsu Shibasaki
Keyword(s):  
Asymmetric Catalysis ◽  
Lewis Acid ◽  
Recent Progress ◽  
Lewis Base ◽  
Pyridine Derivatives ◽  
Asymmetric Catalysts ◽  
Strecker Reaction

Two enantioselective cyanation reactions, the Strecker reaction of ketoimines and the Reissert reaction of pyridine derivatives, promoted by Lewis acid-Lewis base bifunctional asymmetric catalysts are described.

scholarly journals Dichlorodioxomolybdenum(VI) Complexes: Useful and Readily Available Catalysts in Organic Synthesis

Synthesis ◽  
2018 ◽  
Vol 50 (20) ◽  
pp. 4019-4036 ◽  
Author(s):  
Roberto Sanz ◽  
Raquel Hernández-Ruiz
Keyword(s):  
Transition Metal Complexes ◽  
Lewis Acid ◽  
Short Review ◽  
Lewis Base ◽  
Phosphorus Compounds ◽  
Oxidation Reactions ◽  
Organic Transformations ◽  
Reduction Reactions ◽  
Acid Type ◽  
Catalyzed Reactions

Molybdenum(VI) dichloride dioxide (MoO2Cl2), and its addition complexes [MoO2Cl2(L)n; L = neutral ligand], are commercially or easily available and inexpensive transition-metal complexes based on a non-noble metal that can be applied as catalysts for various organic transformations. This short review aims to present the most significant breakthroughs in this field.1 Introduction2 Preparation and Reactivity of MoO2Cl2(L)n Complexes2.1 Synthesis and Structure2.2 Reactivity of Dichlorodioxomolybdenum(VI) Complexes3 Redox Processes Catalyzed by MoO2Cl2(L)n Complexes3.1 Deoxygenation Reactions Using Phosphorus Compounds3.2 Deoxygenation and Hydrosilylation Reactions Using Silanes3.3 Reduction Reactions Using Hydrogen3.4 Deoxygenation Reactions with Boranes and Thiols3.5 Reduction Reactions with Glycols3.6 Oxidation Reactions4 Ambiphilic Reactivity of MoO2Cl2 4.1 Amphoteric Lewis Acid–Lewis Base Catalyzed Reactions4.2 Lewis Acid Type Catalyzed Reactions5 Conclusion and Perspective

ChemInform Abstract: PROTONATION AND LEWIS ACID-LEWIS BASE EQUILIBRIA IN (BIPYRAZINE)MOLYBDENUM AND (BIPYRAZINE)TUNGSTEN TETRACARBONYLS

1985 ◽  
Vol 16 (41) ◽  
Author(s):  
E. S. DODSWORTH ◽  
A. B. P. LEVER ◽  
G. ERYAVEC ◽  
R. J. CRUTCHLEY
Keyword(s):  
Lewis Acid ◽  
Lewis Base
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