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Metallinos C, Iraj Sadraei S, Zhukovskaya N. Diastereoselective Lithiation of N-Silyl-Protected (S)-Tetrahydro-1H-pyrrolo[1,2-c]imidazol-3(2H)-one. HETEROCYCLES 2014. [DOI: 10.3987/com-13-s(s)29] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Mansueto R, Perna FM, Salomone A, Florio S, Capriati V. Dynamic resolution of lithiated ortho-trifluoromethyl styrene oxide and the effect of chiral diamines on the barrier to enantiomerisation. Chem Commun (Camb) 2013; 49:4911-3. [PMID: 23478355 DOI: 10.1039/c3cc40988k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first dynamic thermodynamic resolution of a racemic oxiranyllithium is described with selectivities of up to 82 : 18 from a selection of three types of chiral ligands (seven ligands in total). Both (-)-sparteine and its (+)-surrogate were surprisingly found to increase the enantiomerisation barrier.
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Affiliation(s)
- Rosmara Mansueto
- Dipartimento di Farmacia-Scienze del Farmaco, Università di Bari Aldo Moro, Consorzio C.I.N.M.P.I.S., via E. Orabona 4, I-70125 Bari, Italy
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Li X, Leonori D, Sheikh NS, Coldham I. Synthesis of 1-Substituted Tetrahydroisoquinolines by Lithiation and Electrophilic Quenching Guided by In Situ IR and NMR Spectroscopy and Application to the Synthesis of Salsolidine, Carnegine and Laudanosine. Chemistry 2013; 19:7724-30. [DOI: 10.1002/chem.201301096] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Indexed: 11/06/2022]
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Fournier AM, Nichols CJ, Vincent MA, Hillier IH, Clayden J. Lithium Choreography: Intramolecular Arylations of Carbamate-Stabilised Carbanions and Their Mechanisms Probed by In Situ IR Spectroscopy and DFT Calculations. Chemistry 2012; 18:16478-90. [DOI: 10.1002/chem.201201761] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 08/29/2012] [Indexed: 11/10/2022]
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Beng TK, Woo JS, Gawley RE. Synthetic applications and inversion dynamics of configurationally stable 2-lithio-2-arylpyrrolidines and -piperidines. J Am Chem Soc 2012; 134:14764-71. [PMID: 22881214 PMCID: PMC3443602 DOI: 10.1021/ja306276w] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In diethyl ether, N-Boc-2-lithio-2-arylpiperidines have been found to be configurationally stable at -80 °C, whereas N-Boc-2-lithio-2-arylpyrrolidines are configurationally stable at -60 °C. Several tertiary benzylic carbanions derived from enantioenriched 2-aryl heterocycles have been successfully alkylated or acylated with little to no loss of enantiopurity. The scope of the reactions has been explored. The enantiomerization dynamics of N-Boc-2-lithio-2-phenylpyrrolidine and N-Boc-2-lithio-2-phenylpiperidine have been studied in the presence of different solvents and achiral ligands.
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Affiliation(s)
- Timothy K. Beng
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701
| | - Jin Sun Woo
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701
| | - Robert E. Gawley
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701
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Mitchell EA, Peschiulli A, Lefevre N, Meerpoel L, Maes BUW. Direct α-Functionalization of Saturated Cyclic Amines. Chemistry 2012; 18:10092-142. [DOI: 10.1002/chem.201201539] [Citation(s) in RCA: 356] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Garden JA, Kennedy AR, Mulvey RE, Robertson SD. Ambient temperature zincation of N-Boc pyrrolidine and its solvent dependency. Chem Commun (Camb) 2012; 48:5265-7. [DOI: 10.1039/c2cc31793a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Perna FM, Salomone A, Dammacco M, Florio S, Capriati V. Solvent and TMEDA Effects on the Configurational Stability of Chiral Lithiated Aryloxiranes. Chemistry 2011; 17:8216-25. [DOI: 10.1002/chem.201100351] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Indexed: 11/10/2022]
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Coldham I, Raimbault S, Whittaker DTE, Chovatia PT, Leonori D, Patel JJ, Sheikh NS. Asymmetric substitutions of 2-lithiated N-boc-piperidine and N-Boc-azepine by dynamic resolution. Chemistry 2010; 16:4082-90. [PMID: 20175161 DOI: 10.1002/chem.200903059] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Proton abstraction of N-tert-butoxycarbonyl-piperidine (N-Boc-piperidine) with sBuLi and TMEDA provides a racemic organolithium that can be resolved using a chiral ligand. The enantiomeric organolithiums can interconvert so that a dynamic resolution occurs. Two mechanisms for promoting enantioselectivity in the products are possible. Slow addition of an electrophile such as trimethylsilyl chloride allows dynamic resolution under kinetic control (DKR). This process occurs with high enantioselectivity and is successful by catalysis with substoichiometric chiral ligand (catalytic dynamic kinetic resolution). Alternatively, the two enantiomers of this organolithium can be resolved under thermodynamic control with good enantioselectivity (dynamic thermodynamic resolution, DTR). The best ligands found are based on chiral diamino-alkoxides. Using DTR, a variety of electrophiles can be used to provide an asymmetric synthesis of enantiomerically enriched 2-substituted piperidines, including (after Boc deprotection) the alkaloid (+)-beta-conhydrine. The chemistry was extended, albeit with lower yields, to the corresponding 2-substituted seven-membered azepine ring derivatives.
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Affiliation(s)
- Iain Coldham
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK.
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Gawley RE. Overview of Carbanion Dynamics and Electrophilic Substitutions in Chiral Organolithium Compounds. TOPICS IN STEREOCHEMISTRY 2010; 26:93-133. [PMID: 21804654 PMCID: PMC3145419 DOI: 10.1002/9783906390628.ch3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Robert E Gawley
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas, 72701 USA
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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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Beng TK, Yousaf TI, Coldham I, Gawley RE. Enantiomerization dynamics and a catalytic dynamic resolution of N-trimethylallyl-2-lithiopyrrolidine. J Am Chem Soc 2009; 131:6908-9. [PMID: 19405472 DOI: 10.1021/ja900755a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The barriers to enantiomerization of N-trimethylallyl-2-lithiopyrrolidine have been measured in the presence of sparteine,1, N,N'-diisopropylbispidine, 2, and diaminoalkoxide 3. We have additionally demonstrated a rare example of a catalytic dynamic resolution using either of two ligands, achieving enantiomer ratios of up to 93:7.
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Affiliation(s)
- Timothy K Beng
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, USA
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Oña-Burgos P, Fernández I, Roces L, Torre-Fernández L, García-Granda S, López-Ortiz F. Asymmetric Deprotonation−Substitution of N-Pop-benzylamines Using [RLi/(−)-Sparteine]. Enantioselective Sequential Reactions and Synthesis of N-Heterocycles. Org Lett 2008; 10:3195-8. [DOI: 10.1021/ol801027p] [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)
- Pascual Oña-Burgos
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Ignacio Fernández
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Laura Roces
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Laura Torre-Fernández
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Santiago García-Granda
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
| | - Fernando López-Ortiz
- Área de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120 Almería, Spain, and Departamento de Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain
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Lauru S, Simpkins NS, Gethin D, Wilson C. Enantioselective synthesis of cyclopropylcarboxamides using s-BuLi–sparteine-mediated metallation. Chem Commun (Camb) 2008:5390-2. [DOI: 10.1039/b810441g] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kennedy AR, O'Hara CT. Isolation and characterisation of a (−)-sparteine coordinated mixed alkyl/amido sodium magnesiate, a chiral variant of an important utility ate base. Dalton Trans 2008:4975-7. [DOI: 10.1039/b812085b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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