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Jermaks J, Tallmadge EH, Keresztes I, Collum DB. Lithium Amino Alkoxide-Evans Enolate Mixed Aggregates: Aldol Addition with Matched and Mismatched Stereocontrol. J Am Chem Soc 2018; 140:3077-3090. [PMID: 29457718 PMCID: PMC6059615 DOI: 10.1021/jacs.7b13776] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Building on structural and mechanistic studies of lithiated enolates derived from acylated oxazolidinones (Evans enolates) and chiral lithiated amino alkoxides, we found that amino alkoxides amplify the enantioselectivity of aldol additions. The pairing of enantiomeric series affords matched and mismatched stereoselectivities. The structures of mixed tetramers showing 2:2 and 3:1 (alkoxide-rich) stoichiometries are determined spectroscopically. Rate and computational studies provide a viable mechanistic and stereochemical model based on the direct reaction of the 3:1 mixed tetramers, but they raise unanswered questions for the 2:2 mixed aggregates.
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Affiliation(s)
- Janis Jermaks
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301
| | - Evan H. Tallmadge
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301
| | - Ivan Keresztes
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301
| | - David B. Collum
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301
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2
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Guang J, Liu Q, Hopson R, Kagan G, Li W, Monroe TB, Williard PG. Conformational Polymorphism of Lithium Pinacolone Enolate. J Am Chem Soc 2016; 138:15177-15188. [PMID: 27762552 DOI: 10.1021/jacs.6b08177] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A metastable, polymorphic hexameric crystal structure of lithium pinacolone enolate (LiOPin) is reported along with three preparation methods. NMR-based structural characterization implies that the lithium pinacolate hexamer deaggregates to a tetramer in toluene but retains mainly the hexameric structure in nonaromatic hydrocarbon solvents such as cyclohexane. Moreover, the presence of a small amount of lithium aldolate (LiOA) dramatically influences the aggregation state of LiOPin by forming a mixed aggregate with a 3:1 ratio (LiOPin3·LiOA).
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Affiliation(s)
- Jie Guang
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Qiyong Liu
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Russell Hopson
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Gerald Kagan
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Weibin Li
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Thomas B Monroe
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Paul G Williard
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
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3
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Su C, Hopson R, Williard PG. Influence of Steric Factors on Chiral Lithium Amide Aggregates. J Am Chem Soc 2014; 136:3246-55. [DOI: 10.1021/ja4123957] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Chicheung Su
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912 United States
| | - Russell Hopson
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912 United States
| | - Paul G. Williard
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912 United States
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4
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Dynamics of the Lithium Amide/Alkyllithium Interactions: Mixed Dimers and Beyond. TOP ORGANOMETAL CHEM 2014. [DOI: 10.1007/3418_2014_75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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5
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Ma Y, Stivala CE, Wright AM, Hayton T, Liang J, Keresztes I, Lobkovsky E, Collum DB, Zakarian A. Enediolate-dilithium amide mixed aggregates in the enantioselective alkylation of arylacetic acids: structural studies and a stereochemical model. J Am Chem Soc 2013; 135:16853-64. [PMID: 23654300 PMCID: PMC3818356 DOI: 10.1021/ja403076u] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A combination of X-ray crystallography, (6)Li, (15)N, and (13)C NMR spectroscopies, and density functional theory computations affords insight into the structures and reactivities of intervening aggregates underlying highly selective asymmetric alkylations of carboxylic acid dianions (enediolates) mediated by the dilithium salt of a C2-symmetric chiral tetraamine. Crystallography shows a trilithiated n-butyllithium-dilithiated amide that has dimerized to a hexalithiated form. Spectroscopic studies implicate the non-dimerized trilithiated mixed aggregate. Reaction of the dilithiated amide with the dilithium enediolate derived from phenylacetic acid affords a tetralithio aggregate comprised of the two dianions in solution and the dimerized octalithio form in the solid state. Computational studies shed light on the details of the solution structures and afford a highly predictive stereochemical model.
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Affiliation(s)
- Yun Ma
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University, Ithaca, New York 14853–1301, Telephone: (607)-255-4879; Fax: (850)-644-8281
| | - Craig E. Stivala
- Contribution from the Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106; Telephone: (805)-893-3717; Fax: (805)-893-4120
| | - Ashley M. Wright
- Contribution from the Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106; Telephone: (805)-893-3717; Fax: (805)-893-4120
| | - Trevor Hayton
- Contribution from the Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106; Telephone: (805)-893-3717; Fax: (805)-893-4120
| | - Jun Liang
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University, Ithaca, New York 14853–1301, Telephone: (607)-255-4879; Fax: (850)-644-8281
| | - Ivan Keresztes
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University, Ithaca, New York 14853–1301, Telephone: (607)-255-4879; Fax: (850)-644-8281
| | - Emil Lobkovsky
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University, Ithaca, New York 14853–1301, Telephone: (607)-255-4879; Fax: (850)-644-8281
| | - David B. Collum
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University, Ithaca, New York 14853–1301, Telephone: (607)-255-4879; Fax: (850)-644-8281
| | - Armen Zakarian
- Contribution from the Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106; Telephone: (805)-893-3717; Fax: (805)-893-4120
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6
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Su C, Hopson R, Williard PG. Mixed aggregates of an alkyl lithium reagent and a chiral lithium amide derived from N-ethyl-O-triisopropylsilyl valinol. J Am Chem Soc 2013; 135:14367-79. [PMID: 23980610 DOI: 10.1021/ja406912h] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The crystal structure of a mixed aggregate containing lithiated (S)-N-ethyl-3-methyl-1-(triisopropylsilyloxy)butan-2-amine derived from (S)-valinol and cyclopentyllithium is determined by X-ray diffraction. The mixed aggregate adopts a ladder structure in the solid state. The ladder-type mixed aggregate is also the major species in a toluene-d8 solution containing an approximately 1:1 molar ratio of the lithiated chiral amide to cyclopentyllithium. A variety of NMR experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion coefficient-formula (D-FW) weight correlation analyses and other one- and two-dimensional NMR techniques allowed us to characterize the complex in solution. Solution state structures of the mixed aggregates of n-butyl, sec-butyllithium, isopropyllithium with lithiated (S)-N-ethyl-3-methyl-1-(triisopropylsilyloxy)butan-2-amine are also reported. Identical dimeric, ladder-type, mixed aggregates are the major species at a stoichiometric ratio of 1:1 lithium chiral amide to alkyllithium in toluene-d8 solution for all of the different alkyllithium reagents.
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Affiliation(s)
- Chicheung Su
- Department of Chemistry, Brown University , 324 Brook Street,Providence, Rhode Island 02912, United States
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7
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Harrison-Marchand A, Mongin F. Mixed AggregAte (MAA): A Single Concept for All Dipolar Organometallic Aggregates. 1. Structural Data. Chem Rev 2013; 113:7470-562. [DOI: 10.1021/cr300295w] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anne Harrison-Marchand
- Laboratoire COBRA de l′Université de Rouen, INSA de Rouen, CNRS, UMR 6014 & FR 3038, IRCOF, Rue Tesnière, 76821 Mont St Aignan Cédex, France
| | - Florence Mongin
- Équipe Chimie et Photonique Moléculaires, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1, Bâtiment 10A, case 1003, Avenue du Général Leclerc, 35042 Rennes Cédex, France
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8
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Mongin F, Harrison-Marchand A. Mixed AggregAte (MAA): A Single Concept for All Dipolar Organometallic Aggregates. 2. Syntheses and Reactivities of Homo/HeteroMAAs. Chem Rev 2013; 113:7563-727. [DOI: 10.1021/cr3002966] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Florence Mongin
- Equipe Chimie et Photonique Moléculaires, Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1, Bât. 10A, Case 1003, Campus de Beaulieu, Avenue du Général Leclerc, 35042 Rennes Cédex, France
| | - Anne Harrison-Marchand
- Laboratoire COBRA de l′Université de Rouen, INSA de Rouen, CNRS, UMR 6014 & FR 3038, IRCOF, Rue Tesnière, 76821 Mont St Aignan Cédex, France
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9
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Reich HJ. Role of Organolithium Aggregates and Mixed Aggregates in Organolithium Mechanisms. Chem Rev 2013; 113:7130-78. [DOI: 10.1021/cr400187u] [Citation(s) in RCA: 248] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Hans J. Reich
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
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10
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Han H, Zhao W, Song J, Li C, Wang H. Selectivity of Br/Li Exchange and Deprotonation of 4,4′-Dibromo-3,3′-bithiophene for Synthesis of Symmetrical and Unsymmetrical Dithienoheteroaromatic Rings. J Org Chem 2013; 78:2726-30. [DOI: 10.1021/jo302635y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Hui Han
- Key Lab for Special Functional Materials of Ministry
of Education, Henan University, Kaifeng
475004, China
| | - Wenling Zhao
- Key Lab for Special Functional Materials of Ministry
of Education, Henan University, Kaifeng
475004, China
| | - Jinsheng Song
- Key Lab for Special Functional Materials of Ministry
of Education, Henan University, Kaifeng
475004, China
| | - Chunli Li
- Key Lab for Special Functional Materials of Ministry
of Education, Henan University, Kaifeng
475004, China
| | - Hua Wang
- Key Lab for Special Functional Materials of Ministry
of Education, Henan University, Kaifeng
475004, China
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11
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Harrison-Marchand A, Gérard H, Maddaluno J. Catalytic enantioselective nucleophilic addition of organolithium derivatives: pitfalls and opportunities. NEW J CHEM 2012. [DOI: 10.1039/c2nj40474e] [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]
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12
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Rönnholm P, Gräfenstein J, Norrby PO, Hilmersson G, Nilsson Lill SO. A computational study of the enantioselective addition of n-BuLi to benzaldehyde in the presence of a chiral lithium N,P amide. Org Biomol Chem 2012; 10:2807-14. [DOI: 10.1039/c2ob06910e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Chinkov N, Warm A, Carreira EM. Asymmetric Autocatalysis Enables an Improved Synthesis of Efavirenz. Angew Chem Int Ed Engl 2011; 50:2957-61. [DOI: 10.1002/anie.201006689] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Indexed: 11/09/2022]
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14
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Chinkov N, Warm A, Carreira EM. Eine verbesserte Synthese von Efavirenz durch asymmetrische Autokatalyse. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201006689] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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15
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Fressigné C, Maddaluno J. Are sp Lithiated Carbons More Nucleophilic than sp2or sp3Ones? A Comparative DFT Study of the Condensation of Propynyllithium Aggregates on Formaldehyde. J Org Chem 2010; 75:1427-36. [DOI: 10.1021/jo902315t] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Catherine Fressigné
- Laboratoire de Chimie Théorique, CNRS UMR 7616, Université Pierre et Marie Curie, Case Courrier 137, 4, place Jussieu, 75252 Paris Cedex 05, France
- Institut de Recherche en Chimie Organique Fine, CNRS UMR 6014 & FR 3038, Université de Rouen, 76821-Mont St Aignan Cedex, France
| | - Jacques Maddaluno
- Institut de Recherche en Chimie Organique Fine, CNRS UMR 6014 & FR 3038, Université de Rouen, 76821-Mont St Aignan Cedex, France
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16
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Khartabil HK, Gros PC, Fort Y, Ruiz-López MF. Metalation of Pyridines with nBuLi−Li−Aminoalkoxide Mixed Aggregates: The Origin of Chemoselectivity. J Am Chem Soc 2010; 132:2410-6. [DOI: 10.1021/ja910350q] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hassan K. Khartabil
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - Philippe C. Gros
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - Yves Fort
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - Manuel F. Ruiz-López
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
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17
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Coldham I, Leonori D, Beng TK, Gawley RE. The barrier to enantiomerization and dynamic resolution of N-Boc-2-lithiopiperidine and the effect of TMEDA. Chem Commun (Camb) 2009:5239-41. [PMID: 19707632 DOI: 10.1039/b911024k] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The kinetics of enantiomerization and dynamic thermodynamic resolution (DTR) of N-Boc-2-lithiopiperidine have been measured, revealing significant differences in enthalpy and entropy for these processes and a role for the achiral ligand TMEDA; the racemization and the DTR are catalytic and first order in [TMEDA], and this has implications for asymmetric synthesis with chiral organolithiums.
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Affiliation(s)
- Iain Coldham
- Department of Chemistry, University of Sheffield, Sheffield, UKS3 7HF.
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18
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Luderer MR, Bailey WF, Luderer MR, Fair JD, Dancer RJ, Sommer MB. Asymmetric addition of achiral organomagnesium reagents or organolithiums to achiral aldehydes or ketones: a review. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.tetasy.2009.03.015] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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19
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Khartabil HK, Martins-Costa MTC, Gros PC, Fort Y, Ruiz-López MF. Structure of Mixed Alkyllithium/Lithium Alkoxide Aggregates in Ethereal Solvents. Insights from Combined QM/MM Molecular Dynamics Simulations. J Phys Chem B 2009; 113:6459-67. [DOI: 10.1021/jp809211y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Hassan K. Khartabil
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Marilia T. C. Martins-Costa
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Philippe C. Gros
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Yves Fort
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Manuel F. Ruiz-López
- Equipe Chimie et Biochimie Théoriques and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
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20
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Däschlein C, Strohmann C. Structural Studies on (–)‐Sparteine‐Coordinated Lithiosilanes. Eur J Inorg Chem 2008. [DOI: 10.1002/ejic.200800792] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Christian Däschlein
- Technische Universität Dortmund, Anorganische Chemie, Otto‐Hahn‐Straße 6, 44227 Dortmund
| | - Carsten Strohmann
- Technische Universität Dortmund, Anorganische Chemie, Otto‐Hahn‐Straße 6, 44227 Dortmund
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21
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Knorr R, Menke T, Ferchland K, Mehlstäubl J, Stephenson DS. Microsolvation and 13C-Li NMR coupling. J Am Chem Soc 2008; 130:14179-88. [PMID: 18828636 DOI: 10.1021/ja8026828] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The empirical expression (1)J(CLi) = L[n(a + d)](-1) is proposed; it claims a reciprocal dependence of the NMR coupling constant (1)J((13)C, Li) in a C-Li compound on two factors: (i) the number n of lithium nuclei in bonding contact with the observed carbanion center and (ii) the sum (a + d) of the numbers a of anions and d of donor ligands coordinated at the Li nucleus that generates the observed (1)J(CLi) value. The expression was derived from integrations of separate NMR resonances of coordinated and free monodentate donor ligands (t-BuOMe, Et2O, or THF) in toluene solutions of dimeric and monomeric 2-(alpha-aryl-alpha-lithiomethylidene)-1,1,3,3-tetramethylindan at moderately low temperatures. This unusually slow ligand interchange is ascribed to steric congestion in these compounds, which is further characterized by measurements of nuclear Overhauser correlations and by solid-state structures of the dimers bearing only one donor per lithium atom (d = 1). Increasing microsolvation numbers d are also accompanied by typical changes of the NMR chemical shifts delta (positive for the carbanionic (13)C(alpha), negative for C(para) and p-H). The aforementioned empirical expression for (1)J(CLi) appears to be applicable to other cases of solvated monomeric, dimeric, or tetrameric C-Li compounds (alkyl, alkenyl, alkynyl, and aryl) and even to unsolvated (d approximately 0) trimeric, tetrameric, or hexameric organolithium aggregates, indicating that (1)J(CLi) might serve as a tool for assessing unknown microsolvation numbers. The importance of obtaining evidence about the (13)C NMR C-Li multiplet splitting of both the nonfluxional and fluxional aggregates is emphasized.
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Affiliation(s)
- Rudolf Knorr
- Department of Chemistry and Biochemistry, Ludwig-Maximilians-Universität, Butenandtstrasse 5-13, 81377 München, Germany.
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22
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Khartabil HK, Gros PC, Fort Y, Ruiz-López MF. A Theoretical Study on nBuLi/Lithium Aminoalkoxide Aggregation in Hexane and THF. J Org Chem 2008; 73:9393-402. [DOI: 10.1021/jo8019434] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hassan K. Khartabil
- Equipe Chimie et Biochimie Théoriques, and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Philippe C. Gros
- Equipe Chimie et Biochimie Théoriques, and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Yves Fort
- Equipe Chimie et Biochimie Théoriques, and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
| | - Manuel F. Ruiz-López
- Equipe Chimie et Biochimie Théoriques, and Equipe Synthèse Organométallique et Réactivité, SRSMC, Nancy-University, CNRS, BP 239, 54506 Vandoeuvre-lès-Nancy, France
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23
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Duguet N, Petit SM, Marchand P, Harrison-Marchand A, Maddaluno J. Heterocyclic Lithium Amides as Chiral Ligands for an Enantioselective Hydroxyalkylation with n-BuLi. J Org Chem 2008; 73:5397-409. [DOI: 10.1021/jo8005396] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nicolas Duguet
- Laboratoire des Fonctions Azotées & Oxygénées Complexes de l’IRCOF, UMR CNRS 6014 and FR CNRS 3038, Université de Rouen and INSA de Rouen, 76821 Mont St Aignan Cedex, France
| | - Sylvain M. Petit
- Laboratoire des Fonctions Azotées & Oxygénées Complexes de l’IRCOF, UMR CNRS 6014 and FR CNRS 3038, Université de Rouen and INSA de Rouen, 76821 Mont St Aignan Cedex, France
| | - Philippe Marchand
- Laboratoire des Fonctions Azotées & Oxygénées Complexes de l’IRCOF, UMR CNRS 6014 and FR CNRS 3038, Université de Rouen and INSA de Rouen, 76821 Mont St Aignan Cedex, France
| | - Anne Harrison-Marchand
- Laboratoire des Fonctions Azotées & Oxygénées Complexes de l’IRCOF, UMR CNRS 6014 and FR CNRS 3038, Université de Rouen and INSA de Rouen, 76821 Mont St Aignan Cedex, France
| | - Jacques Maddaluno
- Laboratoire des Fonctions Azotées & Oxygénées Complexes de l’IRCOF, UMR CNRS 6014 and FR CNRS 3038, Université de Rouen and INSA de Rouen, 76821 Mont St Aignan Cedex, France
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Liu J, Li D, Sun C, Williard PG. Analysis of an asymmetric addition with a 2:1 mixed lithium amide/n-butyllithium aggregate. J Org Chem 2008; 73:4045-52. [PMID: 18459811 DOI: 10.1021/jo800592d] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A 2:1 lithium amide/ n-butyllithium aggregate 1 is investigated as an asymmetric addition template in hydrocarbon solvents. Several different chiral lithium amides were synthesized from l-valine and tested in the asymmetric addition of n-BuLi to various aldehydes. Enantiomeric excesses up to 83% were obtained in the case of the addition of n-BuLi to pivaldehyde at -116 degrees C in pentane. (1)H and (13)C INEPT DOSY were utilized to characterize a new trimeric complex 12 between 2 equiv of lithium amide and 1 equiv of lithium alkoxide. This mixed aggregate strongly indicates the possibility of product-induced chirality inhibition that is detrimental to the enantioselectivity of asymmetric addition reaction.
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Affiliation(s)
- Jia Liu
- Department of Chemistry, Brown University, Providence, RI 02912, USA
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25
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Goldfuss B, Steigelmann M, Löschmann T, Schilling G, Rominger F. A dispensable methoxy group? Phenyl fencholate as a chiral modifier of n-butyllithium. Chemistry 2006; 11:4019-23. [PMID: 15861473 DOI: 10.1002/chem.200500158] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Phenyl fenchol forms a 3:1 aggregate with n-butyllithium (3-BuLi), showing unique lithium-HC agostic interactions both in toluene solution (1H,7Li-HOESY) and in the solid state (X-ray analysis). Although methoxy-lithium coordination is characteristic for many mixed aggregates of anisyl fencholates with n-butyllithium, endo-methyl coordination to lithium ions compensates for the missing methoxy groups in 3-BuLi. This gives rise to a different orientation of the fenchane moiety, encapsulating and chirally modifying the butylide unit.
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Affiliation(s)
- B Goldfuss
- Institut für Organische Chemie, Universität zu Köln, Greinstrasse 4, 50939 Köln, Germany.
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Cozzi P, Hilgraf R, Zimmermann N. Acetylenes in Catalysis: Enantioselective Additions to Carbonyl Groups and Imines and Applications Beyond. European J Org Chem 2004. [DOI: 10.1002/ejoc.200400246] [Citation(s) in RCA: 264] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Pier Giorgio Cozzi
- Dipartimento di Chimica “G. Ciamician”, Via Selmi 2, 40126 Bologna, Italy, Fax: (internat.) +39‐051‐2099456
| | - Robert Hilgraf
- Celgene, 4550 Towne Centre Court, San Diego, CA 92121, USA, Fax: (internat.) +1‐858‐795‐4719
| | - Nicole Zimmermann
- Vertex Pharmaceuticals Inc., 11010 Torreyana Road, San Diego, CA 92121, USA, Fax: (internat.) +1‐858‐404‐6726
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Briggs TF, Winemiller MD, Collum DB, Parsons RL, Davulcu AH, Harris GD, Fortunak JM, Confalone PN. Structural and Rate Studies of the 1,2-Additions of Lithium Phenylacetylide to Lithiated Quinazolinones: Influence of Mixed Aggregates on the Reaction Mechanism. J Am Chem Soc 2004; 126:5427-35. [PMID: 15113214 DOI: 10.1021/ja0305813] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The 1,2-addition of lithium phenylacetylide (PhCCLi) to quinazolinones was investigated using a combination of structural and rate studies. (6)Li, (13)C, and (19)F NMR spectroscopies show that deprotonation of quinazolinones and phenylacetylene in THF/pentane solutions with lithium hexamethyldisilazide affords a mixture of lithium quinazolinide/PhCCLi mixed dimer and mixed tetramer along with PhCCLi dimer. Although the mixed tetramer dominates at high mixed aggregate concentrations and low temperatures used for the structural studies, the mixed dimer is the dominant form at the low total mixed aggregate concentrations, high THF concentrations, and ambient temperatures used to investigate the 1,2-addition. Monitoring the reaction rates using (19)F NMR spectroscopy revealed a first-order dependence on mixed dimer, a zeroth-order dependence on THF, and a half-order dependence on the PhCCLi concentration. The rate law is consistent with the addition of a disolvated PhCCLi monomer to the mixed dimer. Investigation of the 1,2-addition of PhCCLi to an O-protected quinazolinone implicates reaction via trisolvated PhCCLi monomers.
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Affiliation(s)
- Timothy F Briggs
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA
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Davlieva MG, Lü JM, Lindeman SV, Kochi JK. Crystallographic Distinction between “Contact” and “Separated” Ion Pairs: Structural Effects on Electronic/ESR Spectra of Alkali-Metal Nitrobenzenides. J Am Chem Soc 2004; 126:4557-65. [PMID: 15070374 DOI: 10.1021/ja049856k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The classic nitrobenzene anion-radical (NB(-*) or nitrobenzenide) is isolated for the first time as pure crystalline alkali-metal salts. The deliberate use of the supporting ligands 18-crown-6 and [2.2.2]cryptand allows the selective formation of contact ion pairs designated as (crown)M(+)NB(-*), where M(+) = K(+), Rb(+), and Cs(+), as well as the separated ion pair K(cryptand)(+)NB(-*)-both series of which are structurally characterized by precise low-temperature X-ray crystallography, ESR analysis, and UV-vis spectroscopy. The unusually delocalized structure of NB(-*) in the separated ion pair follows from the drastically shortened N-C bond and marked quinonoidal distortion of the benzenoid ring to signify complete (95%) electronic conjugation with the nitro substituent. On the other hand, the formation of contact ion pairs results in the substantial decrease of electronic conjugation in inverse order with cation size (K(+) > Rb(+)) owing to increased localization of negative charge from partial (NO(2)) bonding to the alkali-metal cation. Such a loss in electronic conjugation (or reverse charge transfer) may be counterintuitive, but it is in agreement with the distribution of odd-electron spin electron density from the ESR data and with the hypsochromic shift of the characteristic absorption band in the electronic spectra. Most importantly, this crystallographic study underscores the importance of ion-pair structure on the intrinsic property (and thus reactivity) of the component ions-as focused here on the nitrobenzenide anion.
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Affiliation(s)
- Milya G Davlieva
- Department of Chemistry, University of Houston, Houston, Texas 77204-5003, USA
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Choudhury A, Moore JR, Pierce ME, Fortunak JM, Valvis I, Confalone PN. In Situ Recycling of Chiral Ligand and Surplus Nucleophile for a Noncatalytic Reaction: Amplification of Process Throughput in the Asymmetric Addition Step of Efavirenz (DMP 266). Org Process Res Dev 2003. [DOI: 10.1021/op025595s] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anusuya Choudhury
- Chemical Process R&D Department, Process Research Facility, The DuPont Pharmaceuticals Company, Deepwater, New Jersey 08023-0999, U.S.A
| | - James R. Moore
- Chemical Process R&D Department, Process Research Facility, The DuPont Pharmaceuticals Company, Deepwater, New Jersey 08023-0999, U.S.A
| | - Michael E. Pierce
- Chemical Process R&D Department, Process Research Facility, The DuPont Pharmaceuticals Company, Deepwater, New Jersey 08023-0999, U.S.A
| | - Joseph M. Fortunak
- Chemical Process R&D Department, Process Research Facility, The DuPont Pharmaceuticals Company, Deepwater, New Jersey 08023-0999, U.S.A
| | - Ioannis Valvis
- Chemical Process R&D Department, Process Research Facility, The DuPont Pharmaceuticals Company, Deepwater, New Jersey 08023-0999, U.S.A
| | - Pat N. Confalone
- Chemical Process R&D Department, Process Research Facility, The DuPont Pharmaceuticals Company, Deepwater, New Jersey 08023-0999, U.S.A
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Abstract
Extensive cyclizations in hydrocarbon and polar solvents demonstrate a profound solvent sensitivity for intramolecular nitrile anion alkylations. S(N)i cyclizations enforce very precise steric constraints in the transition state, allowing correlation of the cyclization stereochemistry with the orbital orientation of the nitrile anion. Collectively the cyclizations suggest a continuum of nitrile anion transition states, varying from planar to fully pyramidal, that selectively cyclize to cis- and trans-decalins, respectively.
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Affiliation(s)
- Fraser F Fleming
- Department of Chemistry & Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282-1530, USA.
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