51
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Enantioselective Synthesis by Lithiation Adjacent to Oxygen and Electrophile Incorporation. TOP ORGANOMETAL CHEM 2003. [DOI: 10.1007/3-540-36117-0_4] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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52
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Toru T, Nakamura S. Enantioselective Synthesis by Lithiation Adjacent to Sulfur, Selenium or Phosphorus, or without an Adjacent Activating Heteroatom. TOP ORGANOMETAL CHEM 2003. [DOI: 10.1007/3-540-36117-0_6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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53
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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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54
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Nakamura S, Furutani A, Toru T. Highly Enantioselective Reaction of α-Lithio 2-Quinolyl Sulfide Using Chiral Bis(oxazoline)s: A New Synthesis of Enantioenriched Thiols. European J Org Chem 2002. [DOI: 10.1002/1099-0690(200205)2002:10<1690::aid-ejoc1690>3.0.co;2-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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55
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Basu A, Thayumanavan S. Konfigurative Stabilität und Stereoinformationstransfer in Reaktionen Enantiomeren-angereicherter Organolithium-Reagentien. Angew Chem Int Ed Engl 2002. [DOI: 10.1002/1521-3757(20020301)114:5<740::aid-ange740>3.0.co;2-r] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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56
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Arrasate S, Lete E, Sotomayor N. Synthesis of enantiomerically enriched β-amino alcohol derivatives via asymmetric lithiation of O-benzyl carbamates–imine addition using (−)-sparteine complexes. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0957-4166(02)00078-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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57
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Özlügedik M, Kristensen J, Wibbeling B, Fröhlich R, Hoppe D. Nonracemic, Chiral Homoenolate Reagents Derived from (Cycloalk-1-enyl)methyl Carbamates and Evaluation of Their Configurational Stabilities. European J Org Chem 2002. [DOI: 10.1002/1099-0690(20022)2002:3<414::aid-ejoc414>3.0.co;2-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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58
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Asaoka M, Sadayori N, Kawatoh A, Sakurazawa R, Utsumi T, Inagaki M. Diastereoselective Reactions of a Homoenolate Generated from (S)-N-(1-Phenylethyl)-3-(trimethylsilyl)propanamide: Enantioselective Synthesis of (+)-Massoialactone. HETEROCYCLES 2002. [DOI: 10.3987/com-02-s(m)8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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59
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Fredrik Hæffner* and, Brinck T. How Does Methyllithium Invert? A Density Functional Study. Organometallics 2001. [DOI: 10.1021/om010480i] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fredrik Hæffner* and
- Department of Physics, SCFAB, Stockholm University, S 106 91 Stockholm, Sweden, and Physical Chemistry, Royal Institute of Technology, S 100 44 Stockholm, Sweden
| | - Tore Brinck
- Department of Physics, SCFAB, Stockholm University, S 106 91 Stockholm, Sweden, and Physical Chemistry, Royal Institute of Technology, S 100 44 Stockholm, Sweden
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60
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Tomooka K, Shimizu H, Nakai T. On the steric course of transmetallations on enantiomerically defined α-carbamoyloxy organolithiums. J Organomet Chem 2001. [DOI: 10.1016/s0022-328x(01)00641-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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61
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Stratmann O, Kaiser B, Fröhlich R, Meyer O, Hoppe D. The configurational stability of an enantioenriched alpha-thiobenzyllithium derivative and the stereochemical course of its electrophilic substitution reactions; synthesis of enantiomerically pure, tertiary benzylic thiols. Chemistry 2001; 7:423-35. [PMID: 11271529 DOI: 10.1002/1521-3765(20010119)7:2<423::aid-chem423>3.0.co;2-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The lithium compound (S)-7, formed by deprotonation of the (S)-S-1-phenylethyl thiocarbamate (S)-10, is configurationally stable at -70 degrees C. Even at elevated temperatures it racemizes only very slowly. It represents the first essentially enantiopure alpha-thiocarbanion derivative and can be utilized in asymmetric synthesis. Most electrophiles (except proton acids) add to (S)-7 with complete stereoinversion. Cleavage of the substitution products leads to practically enantiopure, tertiary 1-phenylalkanethiols.
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Affiliation(s)
- O Stratmann
- Organisch-Chemisches Institut der Universität Westfälische Wilhelms-Universität Münster, Germany
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62
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Nakamura S, Nakagawa R, Watanabe Y, Toru T. Highly Enantioselective Reactions of Configurationally Labile α-Thioorganolithiums Using Chiral Bis(oxazoline)s via Two Different Enantiodetermining Steps. J Am Chem Soc 2000. [DOI: 10.1021/ja0025191] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shuichi Nakamura
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Ryo Nakagawa
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Yoshihiko Watanabe
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Takeshi Toru
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
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63
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Whisler MC, Vaillancourt L, Beak P. Highly enantioselective syntheses of anti homoaldol products by (-)-sparteine-mediated lithiation/transmetalation/substitution of N-Boc allylic amines. Org Lett 2000; 2:2655-8. [PMID: 10990420 DOI: 10.1021/ol006186o] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text](-)-Sparteine-mediated lithiation/transmetalation/substitution of N-Boc allylic amines provides anti-configured homoaldol precursors in yields of 38-85% and enantiomeric ratios of 83:17-99:1. Subsequent O-protection and hydrolysis allows access to O-protected homoaldol adducts in good yields. The absolute configurations of the homoaldol products have been assigned by calculation of optical rotations and by X-ray crystallography of derivatives. A stereochemical course of reaction for the lithiation/transmetalation/substitution sequence is proposed.
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Affiliation(s)
- M C Whisler
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana 61801, USA
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64
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Gawley RE, Zhang Q, McPhail AT. 2-Lithio- N- BOC-thiazolidines as chiral acyl anion synthons: evaluation of facial stereoselectivity in the addition of chiral organolithiums to aldehydes. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0957-4166(00)00154-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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65
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Gawley RE, Low E, Zhang Q, Harris R. The Steric Course of SE2 Reactions of Unstabilized α-Aminoorganolithiums: Distinguishing between SET and Polar Mechanisms. J Am Chem Soc 2000. [DOI: 10.1021/ja9923235] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Robert E. Gawley
- Contribution from the Department of Chemistry, University of Miami, Coral Gables, Florida 33124-0431
| | - Eddy Low
- Contribution from the Department of Chemistry, University of Miami, Coral Gables, Florida 33124-0431
| | - Qianhui Zhang
- Contribution from the Department of Chemistry, University of Miami, Coral Gables, Florida 33124-0431
| | - Roy Harris
- Contribution from the Department of Chemistry, University of Miami, Coral Gables, Florida 33124-0431
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66
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Direct conversion of Fmoc-protected amines into O-alkyl carbamates by the Mitsunobu reaction: a practical strategy for the solid-phase synthesis of carbamates. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)00088-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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67
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Hammerschmidt F, Hanninger A, Simov BP, Völlenkle H, Werner A. Configurational Stability and Stannylation of Dipole-Stabilised Cyclic Tertiary Benzylic α-Oxycarbanions, which Occurs with Retention or Inversion of Configuration Depending on R and X of R3SnX Used. European J Org Chem 1999. [DOI: 10.1002/(sici)1099-0690(199912)1999:12<3511::aid-ejoc3511>3.0.co;2-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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68
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Derwing C, Frank H, Hoppe D. Chiral Benzyllithium Compounds: High Configurative Stability of (R)- and (S)-1-Lithioindan-1-ylN,N-Diisopropylcarbamate and Unexpected Stereochemical Course of the Substitution Reactions. European J Org Chem 1999. [DOI: 10.1002/(sici)1099-0690(199912)1999:12<3519::aid-ejoc3519>3.0.co;2-n] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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69
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Weisenburger GA, Faibish NC, Pippel DJ, Beak P. Temperature- and Electrophile-Dependent Stereocontrol: A Structural and Mechanistic Investigation of (−)-Sparteine-Mediated Asymmetric Lithiation−Substitution Sequences of N-Boc-N-(p-Methoxyphenyl)cinnamylamine. J Am Chem Soc 1999. [DOI: 10.1021/ja9910560] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gerald A. Weisenburger
- Contribution from the Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, Illinois 61801
| | - Neil C. Faibish
- Contribution from the Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, Illinois 61801
| | - Daniel J. Pippel
- Contribution from the Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, Illinois 61801
| | - Peter Beak
- Contribution from the Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, Illinois 61801
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70
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Generation of allylic and benzylic organolithium reagents from the corresponding ester, amide, carbonate, carbamate and urea derivatives. Tetrahedron 1999. [DOI: 10.1016/s0040-4020(99)00610-9] [Citation(s) in RCA: 27] [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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71
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Gawley RE. A proposal for (slight) modification of the hughes-ingold mechanistic descriptors for substitution reactions. Tetrahedron Lett 1999. [DOI: 10.1016/s0040-4039(99)00780-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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72
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Kawasaki T, Kimachi T. Sparteine-mediated enantioselective [2,3]-Wittig rearrangement of allyl ortho-substituted benzyl ethers and ortho-substituted benzyl prenyl ethers. Tetrahedron 1999. [DOI: 10.1016/s0040-4020(99)00338-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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73
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Deiters A, Hoppe D. Chiral induzierte, mit einer Eliminierung gekoppelte Lithium-En-Reaktion – Synthese von (+)-(3R,4R)-1,2-Dihydromultifiden. Angew Chem Int Ed Engl 1999. [DOI: 10.1002/(sici)1521-3757(19990215)111:4<529::aid-ange529>3.0.co;2-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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74
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The effect of protecting groups on tin-lithium exchange in α-alkoxyalkyltrimethylstannanes. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)02203-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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75
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Behrens K, Fröhlich R, Meyer O, Hoppe D. Enantioselective Lithiation and Substitution of (E)-CinnamylN,N-Diisopropylcarbamate through Use of (−)-Sparteine Complexes. European J Org Chem 1998. [DOI: 10.1002/(sici)1099-0690(199811)1998:11<2397::aid-ejoc2397>3.0.co;2-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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76
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Pippel DJ, Weisenburger GA, Wilson SR, Beak P. Festkörperstruktur des Organolithium-(−)-Spartein-Komplexes η3-N-Boc-N-(p-methoxyphenyl)- 3-phenylallyllithium⋅(−)-Spartein. Angew Chem Int Ed Engl 1998. [DOI: 10.1002/(sici)1521-3757(19980918)110:18<2600::aid-ange2600>3.0.co;2-v] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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77
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Novel N → C acyl migration reaction of acyclic imides: A facile method for α-aminoketones and β-aminoalcohols. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)01093-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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78
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79
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Pippel DJ, Curtis MD, Du H, Beak P. Complex-Induced Proximity Effects: Stereoselective Carbon-Carbon Bond Formation in Chiral Auxiliary Mediated beta-Lithiation-Substitution Sequences of beta-Substituted Secondary Carboxamides. J Org Chem 1998; 63:2-3. [PMID: 11674033 DOI: 10.1021/jo972042k] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel J. Pippel
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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80
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Asaoka M, Tanaka M, Houkawa T, Ueda T, Sakami S, Takei H. Diastereodivergency in the reactions of 3-metallated-2-methylbutanamide. Tetrahedron 1998. [DOI: 10.1016/s0040-4020(97)10292-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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81
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Hoppe D, Kaiser B, Stratmann O, Fröhlich R. Herstellung und Reaktionen einer hoch enantiomerenangereicherten, ungewöhnlich konfigurationsstabilen α-Benzylthiolithiumverbindung. Angew Chem Int Ed Engl 1997. [DOI: 10.1002/ange.19971092412] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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82
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Faibish NC, Park YS, Lee S, Beak P. A Mechanistic and Structural Investigation of the (−)-Sparteine Mediated Asymmetric Benzylic Lithiation Substitution Reactions of N-Boc-N-(p-methoxyphenyl)benzylamine. J Am Chem Soc 1997. [DOI: 10.1021/ja972225o] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Neil C. Faibish
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Yong Sun Park
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Steven Lee
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Peter Beak
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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83
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Hoppe D, Hense T. Enantioselektive Synthese mit Lithium/(−)-Spartein-Carbanion-Paaren. Angew Chem Int Ed Engl 1997. [DOI: 10.1002/ange.19971092105] [Citation(s) in RCA: 200] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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84
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85
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Hammerschmidt F, Hanninger A, Völlenke H. Proof of Inversion of Configuration on Stannylation of a Configurationally Stable, Tertiary Benzyllithium Compound from a Single-Crystal X-Ray Structure Analysis. Chemistry 1997. [DOI: 10.1002/chem.19970031022] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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86
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Thayumanavan S, Basu A, Beak P. Two Different Pathways of Stereoinformation Transfer: Asymmetric Substitutions in the (−)-Sparteine Mediated Reactions of Laterally Lithiated N,N-Diisopropyl-o-ethylbenzamide and N-Pivaloyl-o-ethylaniline. J Am Chem Soc 1997. [DOI: 10.1021/ja970930r] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Thayumanavan
- Contribution from the Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - Amit Basu
- Contribution from the Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - Peter Beak
- Contribution from the Department of Chemistry, University of Illinois, Urbana, Illinois 61801
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87
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Clayden* J, Pink JH. Configurational Stability and Stereospecificity in the Reactions of Amide-Stabilised Organolithiums: A Non-Stereospecific Tin-Lithium Exchange. Tetrahedron Lett 1997. [DOI: 10.1016/s0040-4039(97)00402-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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88
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Park YS, Beak P. Enantioselective Syntheses of α-, β-, and γ-Aryl Amino Acids and Esters. J Org Chem 1997. [DOI: 10.1021/jo9700080] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yong Sun Park
- Department of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| | - Peter Beak
- Department of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
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89
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Seebach D, Sting AR, Hoffmann M. Die Selbstregeneration von Stereozentren (SRS) — Anwendungen, Grenzen und Preisgabe eines Syntheseprinzips. Angew Chem Int Ed Engl 1996. [DOI: 10.1002/ange.19961082304] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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90
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Weisenburger GA, Beak P. α-Lithiation of N-(tert-Butoxycarbonyl)-N-(p- methoxyphenyl)allylamines Mediated by (−)-Sparteine: Enantioselective Syntheses of Either Enantiomer of 3-Substituted Enecarbamates. J Am Chem Soc 1996. [DOI: 10.1021/ja962793o] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gerald A. Weisenburger
- Department of Chemistry University of Illinois at Urbana−Champaign Urbana, Illinois 61801
| | - Peter Beak
- Department of Chemistry University of Illinois at Urbana−Champaign Urbana, Illinois 61801
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91
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Kopach ME, Meyers AI. Metalation-Alkylation of N-Activated Pyrrolidines. Rigorous Proof of Retention for Both Steps. J Org Chem 1996; 61:6764-6765. [PMID: 11667562 DOI: 10.1021/jo961272g] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael E. Kopach
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
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92
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Houkawa T, Ueda T, Sakami S, Asaoka M, Takei H. Complementary diastereoselective β-acylation of α-methylbutanamide. Tetrahedron Lett 1996. [DOI: 10.1016/0040-4039(95)02344-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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93
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Gibson (née Thomas) SE, Potter PCV, Smith MH. Stereocontrolled conversion of secondary benzyl ether tricarbonylchromium(0) complexes into tertiary benzyl ether complexes. Chem Commun (Camb) 1996. [DOI: 10.1039/cc9960002757] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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94
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95
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Hammerschmidt F, Hanninger A. Chiral Carbanions, 1. Configurational Stability and Reactions of α-Acyloxy-Substituted α-Methylbenzyllithium Compounds. ACTA ACUST UNITED AC 1995. [DOI: 10.1002/cber.19951281103] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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96
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Hoppe I, Hoppe D, Boche G, Marsch M, Harms K. Bildung von enantiomerenangereicherten Lithiumindeniden mit (−)-Spartein — Strukturen, stereospezifische Substitution, Einfluß des Lösungsmittels. Angew Chem Int Ed Engl 1995. [DOI: 10.1002/ange.19951071926] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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97
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