151
|
Collins RA, Unruangsri J, Mountford P. Synthesis and rac-lactide ring-opening polymerisation studies of new alkaline earth tetrahydroborate complexes. Dalton Trans 2013; 42:759-69. [DOI: 10.1039/c2dt32151c] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
152
|
Kuzdrowska M, Annunziata L, Marks S, Schmid M, Jaffredo CG, Roesky PW, Guillaume SM, Maron L. Organometallic calcium and strontium borohydrides as initiators for the polymerization of ε-caprolactone and l-lactide: combined experimental and computational investigations. Dalton Trans 2013; 42:9352-60. [DOI: 10.1039/c3dt00037k] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
153
|
Bellham P, Hill MS, Kociok-Köhn G, Liptrot DJ. Alkaline earth alkyl insertion chemistry of in situ generated aminoboranes. Dalton Trans 2013; 42:737-45. [DOI: 10.1039/c2dt31849k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
154
|
|
155
|
Al-Shboul TMA, Görls H, Krieck S, Westerhausen M. Regiospecific Calcium-Mediated Intermolecular Hydrophosphanylation of Butadiynes with Diphenylphosphane Oxide. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201201138] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
156
|
Liu B, Carpentier JF, Sarazin Y. Highly effective alkaline earth catalysts for the sterically governed hydrophosphonylation of aldehydes and nonactivated ketones. Chemistry 2012; 18:13259-64. [PMID: 22976437 DOI: 10.1002/chem.201201489] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 07/17/2012] [Indexed: 11/10/2022]
Affiliation(s)
- Bo Liu
- Organometallics: Materials and Catalysis, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | | | | |
Collapse
|
157
|
Brinkmann C, Barrett AGM, Hill MS, Procopiou PA, Reid S. Alkaline Earth Catalysis of Alkynyl Alcohol Hydroalkoxylation/Cyclization. Organometallics 2012. [DOI: 10.1021/om3008663] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christine Brinkmann
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington,
London, SW7 2AZ U.K
| | - Anthony G. M. Barrett
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington,
London, SW7 2AZ U.K
| | - Michael S. Hill
- Department
of Chemistry, University of Bath, Claverton
Down, Bath, BA2 7AY U.K
| | - Panayiotis A. Procopiou
- GlaxoSmithKline Medicines Research Center, Gunnels Wood Road, Stevenage, Hertfordshire,
SG1 2NY U.K
| | - Stephanie Reid
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington,
London, SW7 2AZ U.K
| |
Collapse
|
158
|
Langer J, Köhler M, Fischer R, Dündar F, Görls H, Westerhausen M. Arylcalcium Iodides in Tetrahydropyran: Solution Stability in Comparison to Aryllithium Reagents. Organometallics 2012. [DOI: 10.1021/om300508w] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jens Langer
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena,
Humboldtstrasse 8, D-07743 Jena, Germany
| | - Mathias Köhler
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena,
Humboldtstrasse 8, D-07743 Jena, Germany
| | - Reinald Fischer
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena,
Humboldtstrasse 8, D-07743 Jena, Germany
| | - Feyza Dündar
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena,
Humboldtstrasse 8, D-07743 Jena, Germany
| | - Helmar Görls
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena,
Humboldtstrasse 8, D-07743 Jena, Germany
| | - Matthias Westerhausen
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena,
Humboldtstrasse 8, D-07743 Jena, Germany
| |
Collapse
|
159
|
Glock C, Görls H, Westerhausen M. Calciate-mediated intermolecular hydroamination of diphenylbutadiyne with secondary anilines. Chem Commun (Camb) 2012; 48:7094-6. [PMID: 22684250 DOI: 10.1039/c2cc32790b] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calciate-mediated intermolecular hydroamination of diphenylbutadiyne with N-phenyl and N-isopropyl-substituted anilines yields E- and Z-isomers of the corresponding 1-anilino-1,4-diphenylbut-1-ene-3-yne. In the case of HNPh(2) solely heterobimetallic K(2)Ca(NPh(2))(4) is able to effectively catalyze this hydroamination reaction in tetrahydrofuran at elevated temperatures.
Collapse
Affiliation(s)
- Carsten Glock
- Friedrich Schiller University, Institute of Inorganic and Analytical Chemistry, Humboldtstrasse 8, D-07743 Jena, Germany
| | | | | |
Collapse
|
160
|
β-Diketiminato-Alkaline Earth Cationic Complexes: Synthesis, Structures, Lactide Polymerization and Unusual Oxidative Reactivity of the Ancillary Ligand. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200183] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
161
|
Liu B, Roisnel T, Carpentier JF, Sarazin Y. When Bigger Is Better: Intermolecular Hydrofunctionalizations of Activated Alkenes Catalyzed by Heteroleptic Alkaline Earth Complexes. Angew Chem Int Ed Engl 2012; 51:4943-6. [DOI: 10.1002/anie.201200364] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 02/17/2012] [Indexed: 11/06/2022]
|
162
|
Liu B, Roisnel T, Carpentier JF, Sarazin Y. When Bigger Is Better: Intermolecular Hydrofunctionalizations of Activated Alkenes Catalyzed by Heteroleptic Alkaline Earth Complexes. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201200364] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
163
|
Arrowsmith M, Hadlington TJ, Hill MS, Kociok-Köhn G. Magnesium-catalysed hydroboration of aldehydes and ketones. Chem Commun (Camb) 2012; 48:4567-9. [PMID: 22473045 DOI: 10.1039/c2cc30565h] [Citation(s) in RCA: 192] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The heteroleptic magnesium alkyl complex [CH{C(Me)NAr}(2)Mg(n)Bu] (Ar = 2,6-(i)Pr(2)C(6)H(3)) is reported as a highly efficient pre-catalyst for the hydroboration of aldehydes and ketones with pinacolborane.
Collapse
Affiliation(s)
- Merle Arrowsmith
- Department of Chemistry, University of Bath, Claverton down, Bath, BA2 7AY, UK
| | | | | | | |
Collapse
|
164
|
Panda TK, Yamamoto K, Yamamoto K, Kaneko H, Yang Y, Tsurugi H, Mashima K. Preparation and Structure of Iminopyrrolyl and Amidopyrrolyl Complexes of Group 2 Metals. Organometallics 2012. [DOI: 10.1021/om201210y] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Tarun K. Panda
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
- Department of Chemistry, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram
502205, Andhra Pradesh, India
| | - Keishi Yamamoto
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Koji Yamamoto
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Kaneko
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Yi Yang
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
165
|
Harder S, Spielmann J. Calcium-mediated hydroboration of alkenes: “Trojan horse” or “true” catalysis? J Organomet Chem 2012. [DOI: 10.1016/j.jorganchem.2011.09.025] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
|
166
|
Arrowsmith M, Hill MS, Kociok-Köhn G, MacDougall DJ, Mahon MF. Beryllium-induced C-N bond activation and ring opening of an N-heterocyclic carbene. Angew Chem Int Ed Engl 2012; 51:2098-100. [PMID: 22266896 DOI: 10.1002/anie.201107836] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 12/27/2011] [Indexed: 11/09/2022]
Affiliation(s)
- Merle Arrowsmith
- Department of Chemistry, University of Bath, Claverton Down, Bath, UK
| | | | | | | | | |
Collapse
|
167
|
Arrowsmith M, Hill MS, Kociok-Köhn G, MacDougall DJ, Mahon MF. Beryllium-Induced CN Bond Activation and Ring Opening of an N-Heterocyclic Carbene. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201107836] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
168
|
Brinkmann C, Barrett AGM, Hill MS, Procopiou PA. Heavier Alkaline Earth Catalysts for the Intermolecular Hydroamination of Vinylarenes, Dienes, and Alkynes. J Am Chem Soc 2012; 134:2193-207. [DOI: 10.1021/ja209135t] [Citation(s) in RCA: 164] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christine Brinkmann
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington,
London SW7 2AZ, U.K
| | - Anthony G. M. Barrett
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington,
London SW7 2AZ, U.K
| | - Michael S. Hill
- Department
of Chemistry, University of Bath, Claverton
Down, Bath BA2 7AY, U.K
| | - Panayiotis A. Procopiou
- GlaxoSmithKline Medicines Research Center, Gunnels Wood Road, Stevenage, Hertfordshire
SG1 2NY, U.K
| |
Collapse
|
169
|
Khandelwal M, Wehmschulte RJ. Cationic organoaluminum compounds as intramolecular hydroamination catalysts. J Organomet Chem 2012. [DOI: 10.1016/j.jorganchem.2011.09.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
170
|
Davin JP, Buffet JC, Spaniol TP, Okuda J. Alkaline earth metal complexes of a chiral polyether as initiator for the ring-opening polymerization of lactide. Dalton Trans 2012; 41:12612-8. [DOI: 10.1039/c2dt31309j] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
171
|
Jochmann P, Davin JP, Maslek S, Spaniol TP, Sarazin Y, Carpentier JF, Okuda J. Allyl strontium compounds: synthesis, molecular structure and properties. Dalton Trans 2012; 41:9176-81. [DOI: 10.1039/c2dt30743j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
172
|
Michel O, Törnroos KW, Maichle‐Mössmer C, Anwander R. Barium Bis(dimethylsilyl)amide – Adduct vs. Oxo Formation. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201101013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Olaf Michel
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany, Fax: +49‐7071‐29‐2436
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway
| | - Karl W. Törnroos
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway
| | - Cäcilia Maichle‐Mössmer
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany, Fax: +49‐7071‐29‐2436
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany, Fax: +49‐7071‐29‐2436
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway
| |
Collapse
|
173
|
Tobisch S. Does a Concerted Non-Insertive Mechanism Prevail over a σ-Insertive Mechanism in Catalytic Cyclohydroamination by Magnesium Tris(oxazolinyl)phenylborate Compounds? A Computational Study. Chemistry 2011; 17:14974-86. [DOI: 10.1002/chem.201101490] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Revised: 08/31/2011] [Indexed: 11/07/2022]
|
174
|
|
175
|
Zhang X, Emge TJ, Hultzsch KC. Ein chiraler Phenoxyamin-Magnesium-Katalysator für die enantioselektive Hydroaminierung/Cyclisierung von Aminoalkenen und die intermolekulare Hydroaminierung von Vinylarenen. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201105079] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
176
|
Zhang X, Emge TJ, Hultzsch KC. A Chiral Phenoxyamine Magnesium Catalyst for the Enantioselective Hydroamination/Cyclization of Aminoalkenes and Intermolecular Hydroamination of Vinyl Arenes. Angew Chem Int Ed Engl 2011; 51:394-8. [DOI: 10.1002/anie.201105079] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
177
|
Ananikov VP, Makarov AV, Beletskaya IP. Catalytic Hydrofunctionalization of Alkynes through PH Bond Addition: The Unique Role of Orientation and Properties of the Phosphorus Group in the Insertion Step. Chemistry 2011; 17:12623-30. [DOI: 10.1002/chem.201101898] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Indexed: 11/08/2022]
|
178
|
Jochmann P, Spaniol TP, Chmely SC, Hanusa TP, Okuda J. Preparation, Structure, and Ether Cleavage of a Mixed Hapticity Allyl Compound of Calcium. Organometallics 2011. [DOI: 10.1021/om200749f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Phillip Jochmann
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Thomas P. Spaniol
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Stephen C. Chmely
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Timothy P. Hanusa
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Jun Okuda
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| |
Collapse
|
179
|
Blake MP, Kaltsoyannis N, Mountford P. Heterobimetallic Complexes Containing Ca–Fe or Yb–Fe Bonds: Synthesis and Molecular and Electronic Structures of [M{CpFe(CO)2}2(THF)3]2 (M = Ca or Yb). J Am Chem Soc 2011; 133:15358-61. [DOI: 10.1021/ja207487j] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew P. Blake
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, U.K
| | - Nikolas Kaltsoyannis
- Christopher Ingold Laboratories, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - Philip Mountford
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, U.K
| |
Collapse
|
180
|
Blair VL, Clegg W, Kennedy AR, Livingstone Z, Russo L, Hevia E. Magnesium-Mediated Benzothiazole Activation: A Room-Temperature Cascade of CH Deprotonation, CC Coupling, Ring-Opening, and Nucleophilic Addition Reactions. Angew Chem Int Ed Engl 2011; 50:9857-60. [DOI: 10.1002/anie.201103275] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Indexed: 11/11/2022]
|
181
|
Blair VL, Clegg W, Kennedy AR, Livingstone Z, Russo L, Hevia E. Magnesium-Mediated Benzothiazole Activation: A Room-Temperature Cascade of CH Deprotonation, CC Coupling, Ring-Opening, and Nucleophilic Addition Reactions. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201103275] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
182
|
Yang D, Ding Y, Wu H, Zheng W. Synthesis and Structural Characterization of Alkaline-Earth-Metal Bis(amido)silane and Lithium Oxobis(aminolato)silane Complexes. Inorg Chem 2011; 50:7698-706. [DOI: 10.1021/ic200748z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Dongming Yang
- Institute of Organic Chemistry, Shanxi Normal University, 1 Gongyuan Street, Linfen, Shanxi Province 041004, People’s Republic of China
| | - Yuqiang Ding
- School of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Haishun Wu
- Institute of Organic Chemistry, Shanxi Normal University, 1 Gongyuan Street, Linfen, Shanxi Province 041004, People’s Republic of China
| | - Wenjun Zheng
- Institute of Organic Chemistry, Shanxi Normal University, 1 Gongyuan Street, Linfen, Shanxi Province 041004, People’s Republic of China
| |
Collapse
|
183
|
Langer J, Al-Shboul TMA, Younis FM, Görls H, Westerhausen M. Coordination Behavior and Coligand-Dependent cis/trans Isomerism of Calcium Bis(diphenylphosphanides). Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100241] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
184
|
Sarazin Y, Liu B, Roisnel T, Maron L, Carpentier JF. Discrete, solvent-free alkaline-earth metal cations: metal···fluorine interactions and ROP catalytic activity. J Am Chem Soc 2011; 133:9069-87. [PMID: 21545119 DOI: 10.1021/ja2024977] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Efficient protocols for the syntheses of well-defined, solvent-free cations of the large alkaline-earth (Ae) metals (Ca, Sr, Ba) and their smaller Zn and Mg analogues have been designed. The reaction of 2,4-di-tert-butyl-6-(morpholinomethyl)phenol ({LO(1)}H), 2-{[bis(2-methoxyethyl)amino]methyl}-4,6-di-tert-butylphenol ({LO(2)}H), 2-[(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)methyl]-4,6-di-tert-butylphenol ({LO(3)}H), and 2-[(1,4,7,10-tetraoxa-13-azacyclo-pentadecan-13-yl)methyl]-1,1,1,3,3,3-hexafluoropropan-2-ol ({RO(3)}H) with [H(OEt(2))(2)](+)[H(2)N{B(C(6)F(5))(3)}(2)](-) readily afforded the doubly acidic pro-ligands [{LO(1)}HH](+)[X](-) (1), [{LO(2)}HH](+)[X](-) (2), [{LO(3)}HH](+)[X](-) (3), and [{RO(3)}HH](+)[X](-) (4) ([X](-) = [H(2)N{B(C(6)F(5))(3)}(2)](-)). The addition of 2 to Ca[N(SiMe(3))(2)](2)(THF)(2) and Sr[N(SiMe(3))(2)](2)(THF)(2) yielded [{LO(2)}Ca(THF)(0.5)](+)[X](-) (5) and [{LO(2)}Sr(THF)](+)[X](-) (6), respectively. Alternatively, 5 could also be prepared upon treatment of {LO(2)}CaN(SiMe(3))(2) (7) with [H(OEt(2))(2)](+)[X](-). Complexes [{LO(3)}M](+)[X](-) (M = Zn, 8; Mg, 9; Ca, 10; Sr, 11; Ba, 12) and [{RO(3)}M](+)[X](-) (M = Zn, 13; Mg, 14; Ca, 15; Sr, 16; Ba, 17) were synthesized in high yields (70-90%) by reaction of 3 or 4 with the neutral precursors M[N(SiMe(3))(2)](2)(THF)(x) (M = Zn, Mg, x = 0; M = Ca, Sr, Ba, x = 2). All compounds were fully characterized by spectroscopic methods, and the solid-sate structures of compounds 1, 3, 7, 8, 13, 14, {15}(4)·3CD(2)Cl(2), {16}(4)·3CD(2)Cl(2), and {{17}(4)·EtOH}·3CD(2)Cl(2) were determined by X-ray diffraction crystallography. Whereas the complexes are monomeric in the case of Zn and Mg, they form bimetallic cations in the case of Ca, Sr and Ba; there is no contact between the metal and the weakly coordinating anion. In all metal complexes, the multidentate ligand is κ(6)-coordinated to the metal. Strong intramolecular M···F secondary interactions between the metal and F atoms from the ancillary ligands are observed in the structures of {15}(4)·3CD(2)Cl(2), {16}(4)·3CD(2)Cl(2), and {{17}(4)·EtOH}·3CD(2)Cl(2). VT (19)F{(1)H} NMR provided no direct evidence that these interactions are maintained in solution; nevertheless, significant Ae···F energies of stabilization of 25-26 (Ca, Ba) and 40 kcal·mol(-1) (Sr) were calculated by NBO analysis on DFT-optimized structures. The identity and integrity of the cationic complexes are preserved in solution in the presence of an excess of alcohol (BnOH, (i)PrOH) or L-lactide (L-LA). Efficient binary catalytic systems for the immortal ring-opening polymerization of L-LA (up to 3,000 equiv) are produced upon addition of an excess (5-50 equiv) of external protic nucleophilic agents (BnOH, (i)PrOH) to 8-12 or 13-17. PLLAs with M(n) up to 35,000 g·mol(-1) were produced in a very controlled fashion (M(w)/M(n) ≈ 1.10-1.20) and without epimerization. In each series of catalysts, the following order of catalytic activity was established: Mg ≪ Zn < Ca < Sr ≈ Ba; also, Ae complexes supported by the aryloxide ligand are more active than their parents supported by the fluorinated alkoxide ancillary, possibly owing to the presence of Ae···F interactions in the latter case. The rate law -d[L-LA]/dt = k(p)·[L-LA](1.0)·[16](1.0)·[BnOH](1.0) was established by NMR kinetic investigations, with the corresponding activation parameters ΔH(++) = 14.8(5) kcal·mol(-1) and ΔS(++) = -7.6(2.0) cal·K(-1)·mol(-1). DFT calculations indicated that the observed order of catalytic activity matches an increase of the L-LA coordination energy onto the cationic metal centers with parallel decrease of the positive metal charge.
Collapse
Affiliation(s)
- Yann Sarazin
- UMR 6226 Sciences Chimiques de Rennes, Université de Rennes 1-CNRS, Campus de Beaulieu, 35042 Rennes Cedex, France.
| | | | | | | | | |
Collapse
|
185
|
Michel O, Törnroos KW, Maichle-Mössmer C, Anwander R. Peralkylated Barium Complexes. Chemistry 2011; 17:4964-7. [DOI: 10.1002/chem.201100460] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 02/10/2011] [Indexed: 11/10/2022]
|
186
|
Sarish SP, Nembenna S, Nagendran S, Roesky HW. Chemistry of soluble β-diketiminatoalkaline-earth metal complexes with M-X bonds (M=Mg, Ca, Sr; X=OH, Halides, H). Acc Chem Res 2011; 44:157-70. [PMID: 21247094 DOI: 10.1021/ar100103h] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Victor Grignard's Nobel Prize-winning preparation of organomagnesium halides (Grignard reagents) marked the formal beginning of organometallic chemistry with alkaline earth metals. Further development of this invaluable synthetic route, RX+Mg→RMgX, with the heavier alkaline earth metals (Ca and Sr) was hampered by limitations in synthetic methodologies. Moreover, the lack of suitable ligands for stabilizing the reactive target molecules, particularly with the more electropositive Ca and Sr, was another obstacle. The absence in the literature, until just recently, of fundamental alkaline earth metal complexes with M-H, M-F, and M-OH (where M is the Group 2 metal Mg, Ca, or Sr) bonds amenable for organometallic reactions is remarkable. The progress in isolating various unstable compounds of p-block elements with β-diketiminate ligands was recently applied to Group 2 chemistry. The monoanionic β-diketiminate ligands are versatile tools for addressing synthetic challenges, as amply demonstrated with alkaline earth complexes: the synthesis and structural characterization of soluble β-diketiminatocalcium hydroxide, β-diketiminatostrontium hydroxide, and β-diketiminatocalcium fluoride are just a few examples of our contribution to this area of research. To advance the chemistry beyond synthesis, we have investigated the reactivity and potential for applications of these species, for example, through the demonstration of dip coating surfaces with CaCO(3) and CaF(2) with solutions of the calcium hydroxide and calcium fluoride complexes, respectively. In this Account, we summarize some recent developments in alkaline earth metal complex chemistry, particularly of Mg, Ca, and Sr, through the utilization of β-diketiminate ligands. We focus on results generated in our laboratory but give due mention to work from other groups as well. We also highlight the closely related chemistry of the Group 12 element Zn, as well as the important chemistry developed by other groups using the complexes we have reported. Although Mg and Ca are more abundant in living organisms, no other metal has as many biological functions as Zn. Thus Zn, the nontoxic alternative to the heavier Group 12 elements Cd and Hg, occupies a unique position ripe for further exploration.
Collapse
Affiliation(s)
| | - Sharanappa Nembenna
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Selvarajan Nagendran
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi 110 016, India
| | - Herbert W. Roesky
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| |
Collapse
|
187
|
Jochmann P, Maslek S, Spaniol TP, Okuda J. Allyl Calcium Compounds: Synthesis and Structure of Bis(η3-1-alkenyl)calcium. Organometallics 2011. [DOI: 10.1021/om200012k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Phillip Jochmann
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Stefanie Maslek
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Thomas P. Spaniol
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Jun Okuda
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| |
Collapse
|
188
|
Arrowsmith M, Hill MS, Kociok-Köhn G. Suppression of Schlenk Equilibration and Heavier Alkaline Earth Alkyl Catalysis: A Dearomatization Strategy. Organometallics 2011. [DOI: 10.1021/om200028m] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Merle Arrowsmith
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Michael S. Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | | |
Collapse
|
189
|
Arrowsmith M, Crimmin MR, Barrett AGM, Hill MS, Kociok-Köhn G, Procopiou PA. Cation Charge Density and Precatalyst Selection in Group 2-Catalyzed Aminoalkene Hydroamination. Organometallics 2011. [DOI: 10.1021/om101063m] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Merle Arrowsmith
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
| | - Mark R. Crimmin
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, U.K
| | - Anthony G. M. Barrett
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, U.K
| | - Michael S. Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
| | | | - Panayiotis A. Procopiou
- GlaxoSmithKline Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, U.K
| |
Collapse
|
190
|
Al-Shboul TM, Pálfi VK, Yu L, Kretschmer R, Wimmer K, Fischer R, Görls H, Reiher M, Westerhausen M. Catalytic synthesis of vinylphosphanes via calcium-mediated intermolecular hydrophosphanylation of alkynes and butadiynes. J Organomet Chem 2011. [DOI: 10.1016/j.jorganchem.2010.08.058] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
191
|
Cushion MG, Mountford P. Cationic and charge-neutral calcium tetrahydroborate complexes and their use in the controlled ring-opening polymerisation of rac-lactide. Chem Commun (Camb) 2011; 47:2276-8. [DOI: 10.1039/c0cc04348f] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
192
|
Hill MS, Kociok-Köhn G, MacDougall DJ, Mahon MF, Weetman C. Magnesium hydrides and the dearomatisation of pyridine and quinoline derivatives. Dalton Trans 2011; 40:12500-9. [DOI: 10.1039/c1dt11235j] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
193
|
Buffet JC, Davin JP, Spaniol TP, Okuda J. Alkaline earth metal amide complexes containing a cyclen-derived (NNNN) macrocyclic ligand: synthesis, structure, and ring-opening polymerization activity towards lactide monomers. NEW J CHEM 2011. [DOI: 10.1039/c1nj20259f] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
194
|
Neal SR, Ellern A, Sadow AD. Optically active, bulky tris(oxazolinyl)borato magnesium and calcium compounds for asymmetric hydroamination/cyclization. J Organomet Chem 2011. [DOI: 10.1016/j.jorganchem.2010.08.057] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
195
|
|
196
|
Swartz II DL, Staples RJ, Odom AL. Synthesis and hydroamination catalysis with 3-aryl substituted pyrrolyl and dipyrrolylmethane titanium(iv) complexes. Dalton Trans 2011; 40:7762-8. [DOI: 10.1039/c1dt10127g] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
197
|
Sarazin Y, Roşca D, Poirier V, Roisnel T, Silvestru A, Maron L, Carpentier JF. Bis(dimethylsilyl)amide Complexes of the Alkaline-Earth Metals Stabilized by β-Si−H Agostic Interactions: Synthesis, Characterization, and Catalytic Activity. Organometallics 2010. [DOI: 10.1021/om100908q] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yann Sarazin
- Catalysis and Organometallics, UMR CNRS 6226−Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Dragoş Roşca
- Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, RO-400028, Cluj-Napoca, Romania
| | - Valentin Poirier
- Catalysis and Organometallics, UMR CNRS 6226−Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Thierry Roisnel
- Catalysis and Organometallics, UMR CNRS 6226−Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Anca Silvestru
- Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, RO-400028, Cluj-Napoca, Romania
| | - Laurent Maron
- LPCNO, UMR 5215, Université de Toulouse-CNRS, UPS135 Avenue de Rangueil, 31077 Toulouse, France
| | - Jean-François Carpentier
- Catalysis and Organometallics, UMR CNRS 6226−Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| |
Collapse
|
198
|
Harder S. From limestone to catalysis: application of calcium compounds as homogeneous catalysts. Chem Rev 2010; 110:3852-76. [PMID: 20420358 DOI: 10.1021/cr9003659] [Citation(s) in RCA: 496] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sjoerd Harder
- Anorganische Chemie, Universität Duisburg-Essen, 45117 Essen, Germany.
| |
Collapse
|
199
|
Jochmann P, Dols TS, Spaniol TP, Perrin L, Maron L, Okuda J. Insertion von Pyridin in die Calcium-Allyl-Bindung: regioselektive Bildung von 1,4-Dihydropyridinen und C-H-Aktivierung. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201003704] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
200
|
Arrowsmith M, Hill MS, Kociok-Köhn G. Dearomatization and C−H Deprotonation with Heavier Group 2 Alkyls: Does Size Matter? Organometallics 2010. [DOI: 10.1021/om100649z] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Merle Arrowsmith
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
| | - Michael S. Hill
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
| | | |
Collapse
|