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De Sarkar S, Biswas A, Samanta RC, Studer A. Catalysis with N-Heterocyclic Carbenes under Oxidative Conditions. Chemistry 2013; 19:4664-78. [DOI: 10.1002/chem.201203707] [Citation(s) in RCA: 411] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Indexed: 11/05/2022]
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152
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153
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Diederich F. 125 Years of Chemistry in the Mirror of “Angewandte”. Angew Chem Int Ed Engl 2013; 52:2714-42. [DOI: 10.1002/anie.201300056] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Indexed: 01/09/2023]
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154
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Lian Y, Huber T, Hesp KD, Bergman RG, Ellman JA. Rhodium(III)-catalyzed alkenyl C-H bond functionalization: convergent synthesis of furans and pyrroles. Angew Chem Int Ed Engl 2013; 52:629-33. [PMID: 23172703 PMCID: PMC3770945 DOI: 10.1002/anie.201207995] [Citation(s) in RCA: 158] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Indexed: 11/10/2022]
Abstract
Ring in the new: a new annulation for the efficient synthesis of substituted furans and pyrroles is reported. The Rh(III) -catalyzed reaction of O-methyl α,β-unsaturated oximes with aldehydes and N-tosyl imines affords secondary alcohol and amine intermediates, respectively. Cyclization and aromatization occurs under the reaction conditions to provide access to biologically relevant furans and pyrroles in good yields. Cp*=C(5)Me(5), DCE=1,2-dichloroethane, THF=tetrahydrofuran.
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Affiliation(s)
- Yajing Lian
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT 06520 (USA)
| | - Tatjana Huber
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT 06520 (USA)
| | - Kevin D. Hesp
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT 06520 (USA)
| | - Robert G. Bergman
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1416 (USA), Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (USA)
| | - Jonathan A. Ellman
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT 06520 (USA)
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155
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157
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Lian Y, Huber T, Hesp KD, Bergman RG, Ellman JA. Rhodium(III)-Catalyzed Alkenyl CH Bond Functionalization: Convergent Synthesis of Furans and Pyrroles. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201207995] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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158
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Gladow D, Reissig HU. Synthesis of Perfluoroalkyl-Substitutedγ-Lactones and 4,5-Dihydropyridazin-3(2H)-onesviaDonorAcceptor Cyclopropanes. Helv Chim Acta 2012. [DOI: 10.1002/hlca.201200413] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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159
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Denmark SE, Wilson TW. Silyl ketene imines: highly versatile nucleophiles for catalytic, asymmetric synthesis. Angew Chem Int Ed Engl 2012; 51:9980-92. [PMID: 22968901 DOI: 10.1002/anie.201202139] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2012] [Indexed: 11/09/2022]
Abstract
This Minireview provides an overview on the development of silyl ketene imines and their recent applications in catalytic, enantioselective reactions. The unique structure of the ketene imine allows a diverse range of reactivity patterns and provides solutions to existing challenges in the enantioselective construction of quaternary stereogenic carbon centers and cross-benzoin adducts. A variety of reactions for which silyl ketene imines have been applied are presented with an overall goal of inspiring new uses for these underutilized nucleophiles.
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Affiliation(s)
- Scott E Denmark
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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160
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Denmark SE, Wilson TW. Silylketenimine - vielseitige Nucleophile für die katalytische asymmetrische Synthese. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201202139] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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161
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Maji B, Mayr H. Structures and Reactivities of O-Methylated Breslow Intermediates. Angew Chem Int Ed Engl 2012; 51:10408-12. [DOI: 10.1002/anie.201204524] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Indexed: 11/12/2022]
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162
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163
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Umpolung of Fluoroform by CF Bond Activation: Direct Difluoromethylation of Lithium Enolates. Angew Chem Int Ed Engl 2012; 51:9535-8. [DOI: 10.1002/anie.201203588] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 07/04/2012] [Indexed: 11/07/2022]
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164
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Iida T, Hashimoto R, Aikawa K, Ito S, Mikami K. Umpolung of Fluoroform by CF Bond Activation: Direct Difluoromethylation of Lithium Enolates. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201203588] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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165
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Sun ZX, Cheng Y. One-Step Formation both of C-N and of C-O Bonds of N-Alkoxyamides through NHC-Catalyzed Three-Component Reactions of Enals, Nitrosoarenes, and Enones. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200525] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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166
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167
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Mahapatra S, Carter RG. Enantioselective total synthesis of amphidinolide F. Angew Chem Int Ed Engl 2012; 51:7948-51. [PMID: 22767517 DOI: 10.1002/anie.201203935] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Indexed: 11/07/2022]
Affiliation(s)
- Subham Mahapatra
- Chemistry Department, Oregon State University, Corvallis, OR 97331, USA
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168
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Zhang B, Feng P, Sun LH, Cui Y, Ye S, Jiao N. N-Heterocyclic Carbene-Catalyzed Homoenolate Additions with N-Aryl Ketimines as Electrophiles: Efficient Synthesis of Spirocyclic γ-Lactam Oxindoles. Chemistry 2012; 18:9198-203. [DOI: 10.1002/chem.201201375] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2012] [Indexed: 11/12/2022]
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169
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Loh CCJ, Enders D. Merging Organocatalysis and Gold Catalysis-A Critical Evaluation of the Underlying Concepts. Chemistry 2012; 18:10212-25. [DOI: 10.1002/chem.201200287] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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170
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Smirnov VO, Khomutova YA, Tartakovsky VA, Ioffe SL. C-C Coupling of Acyclic Nitronates with Silyl Ketene Acetals under Silyl Triflate Catalysis: Reactivity Umpolung of Aliphatic Nitro Compounds. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200239] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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171
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Maji B, Horn M, Mayr H. Nucleophilic Reactivities of Deoxy Breslow Intermediates: How Does Aromaticity Affect the Catalytic Activities of N-Heterocyclic Carbenes? Angew Chem Int Ed Engl 2012; 51:6231-5. [DOI: 10.1002/anie.201202327] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Indexed: 11/05/2022]
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172
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Maji B, Horn M, Mayr H. Nucleophile Reaktivitäten von Desoxy-Breslow-Intermediaten: Wie beeinflusst Aromatizität die katalytische Aktivität N-heterocyclischer Carbene? Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201202327] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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173
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Vora HU, Wheeler P, Rovis T. Exploiting Acyl and Enol Azolium Intermediates via NHeterocyclic Carbene Catalyzed Reactions of Alpha-Reducible Aldehydes. Adv Synth Catal 2012; 354:1617-1639. [PMID: 23538785 DOI: 10.1002/adsc.201200031] [Citation(s) in RCA: 345] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
N-heterocyclic carbenes are well known for their role in catalyzing benzoin and Stetter reactions: the generation of acyl anion equivalents from simple aldehydes to react with a variety of electrophiles. However, when an aldehyde bearing a leaving group or unsaturation adjacent to the acyl anion equivalent is subjected to an NHC, a new avenue of reactivity is unlocked, leading to a number of novel transformations which can generate highly complex products from simple starting materials, many of which are assembled through unconventional bond disconnections. The field of these new reactions - those utilizing α-reducible aldehydes to access previously unexplored catalytic intermediates - has expanded rapidly in the past eight years. This review aims to provide the reader with a historical perspective on the underlying discoveries that led to the current state of the art, a mechanistic description of these reactions, and a summary of the recent advances in this area.
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174
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Kim SH, Kim KH, Kim JN. Construction of 1,2,5-Tricarbonyl Compounds using Methyl Cyanoacetate as a Glyoxylate Anion Synthon Combined with Copper(I) Iodide-Catalyzed Aerobic Oxidation. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100431] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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175
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Grossmann A, Enders D. Durch N-heterocyclische Carbene katalysierte Dominoreaktionen. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201105415] [Citation(s) in RCA: 318] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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176
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Grossmann A, Enders D. N-Heterocyclic Carbene Catalyzed Domino Reactions. Angew Chem Int Ed Engl 2011; 51:314-25. [DOI: 10.1002/anie.201105415] [Citation(s) in RCA: 880] [Impact Index Per Article: 67.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Indexed: 11/11/2022]
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177
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Zhao F, Zhang W, Yang Y, Pan Y, Chen W, Liu H, Yan L, Tan CH, Jiang Z. Synthesis of Sulfur-Substituted α-Stereogenic Amides and Ketones: Highly Enantioselective Sulfa-Michael Additions of 1,4-Dicarbonylbut-2-enes. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100227] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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178
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Zimmer LE, Sparr C, Gilmour R. Konformative Fluoreffekte in der Organokatalyse: eine neuartige Strategie zum molekularen Design. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201102027] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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179
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Zimmer LE, Sparr C, Gilmour R. Fluorine conformational effects in organocatalysis: an emerging strategy for molecular design. Angew Chem Int Ed Engl 2011; 50:11860-71. [PMID: 21953782 DOI: 10.1002/anie.201102027] [Citation(s) in RCA: 239] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Indexed: 11/12/2022]
Abstract
Molecular design strategies that profit from the intrinsic stereoelectronic and electrostatic effects of fluorinated organic molecules have mainly been restricted to bio-organic chemistry. Indeed, many fluorine conformational effects remain academic curiosities with no immediate application. However, the renaissance of organocatalysis offers the possibility to exploit many of these well-described phenomena for molecular preorganization. In this minireview, we highlight examples of catalyst refinement by introduction of an aliphatic C-F bond which functions as a chemically inert steering group for conformational control.
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Affiliation(s)
- Lucie E Zimmer
- ETH Zürich, Laboratorium für Organische Chemie, Departement Chemie und Angewandte Biowissenschaften, Wolfgang-Pauli-Str. 10, CH-8093 Zürich, Switzerland
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180
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Lu B, Luo Y, Liu L, Ye L, Wang Y, Zhang L. Umpolung reactivity of indole through gold catalysis. Angew Chem Int Ed Engl 2011; 50:8358-62. [PMID: 21761530 PMCID: PMC3465525 DOI: 10.1002/anie.201103014] [Citation(s) in RCA: 202] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Indexed: 11/09/2022]
Affiliation(s)
| | | | | | | | | | - Liming Zhang
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California (USA)
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181
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Piel I, Pawelczyk MD, Hirano K, Fröhlich R, Glorius F. A Family of Thiazolium Salt Derived N-Heterocyclic Carbenes (NHCs) for Organocatalysis: Synthesis, Investigation and Application in Cross-Benzoin Condensation. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100870] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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182
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Sparr C, Gilmour R. Cyclopropyl Iminium Activation: Reactivity Umpolung in Enantioselective Organocatalytic Reaction Design. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201103360] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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183
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Sparr C, Gilmour R. Cyclopropyl Iminium Activation: Reactivity Umpolung in Enantioselective Organocatalytic Reaction Design. Angew Chem Int Ed Engl 2011; 50:8391-5. [DOI: 10.1002/anie.201103360] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 06/30/2011] [Indexed: 11/06/2022]
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184
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Lu B, Luo Y, Liu L, Ye L, Wang Y, Zhang L. Umpolung Reactivity of Indole through Gold Catalysis. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201103014] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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185
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Maji B, Breugst M, Mayr H. N-Heterocyclic Carbenes: Organocatalysts with Moderate Nucleophilicity but Extraordinarily High Lewis Basicity. Angew Chem Int Ed Engl 2011; 50:6915-9. [DOI: 10.1002/anie.201102435] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Indexed: 11/07/2022]
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186
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Maji B, Breugst M, Mayr H. N-Heterocyclische Carbene: Organokatalysatoren mit mäßiger Nucleophilie, aber außerordentlich hoher Lewis-Basizität. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201102435] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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187
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Abstract
The use of N-heterocyclic carbenes as catalysts for organic transformations has received increased attention in the past 10 years. A discussion of catalyst development and nucleophilic characteristics precedes a description of recent advancements and new reactions using N-heterocyclic carbenes in catalysis.
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188
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Alonso B, Reyes E, Carrillo L, Vicario JL, Badía D. Organocatalytic Enantioselective Formal Conjugate Addition of a Hydroxymoyl Anion to α,β‐Unsaturated Aldehydes. Chemistry 2011; 17:6048-51. [DOI: 10.1002/chem.201100605] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Indexed: 11/11/2022]
Affiliation(s)
- Beatriz Alonso
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/, Euskal Herriko Unibertsitatea (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain), Fax: (+34) 94‐601‐5454
| | - Efraím Reyes
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/, Euskal Herriko Unibertsitatea (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain), Fax: (+34) 94‐601‐5454
| | - Luisa Carrillo
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/, Euskal Herriko Unibertsitatea (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain), Fax: (+34) 94‐601‐5454
| | - Jose L. Vicario
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/, Euskal Herriko Unibertsitatea (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain), Fax: (+34) 94‐601‐5454
| | - Dolores Badía
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/, Euskal Herriko Unibertsitatea (UPV/EHU), P.O. Box 644, 48080 Bilbao (Spain), Fax: (+34) 94‐601‐5454
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189
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Streuff J. A titanium(III)-catalyzed redox umpolung reaction for the reductive cross-coupling of enones with acrylonitriles. Chemistry 2011; 17:5507-10. [PMID: 21488110 DOI: 10.1002/chem.201100501] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Jan Streuff
- Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104 Freiburg i. Br., Germany.
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190
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Moore JL, Silvestri AP, de Alaniz JR, DiRocco DA, Rovis T. Mechanistic investigation of the enantioselective intramolecular stetter reaction: proton transfer is the first irreversible step. Org Lett 2011; 13:1742-5. [PMID: 21355598 PMCID: PMC3064720 DOI: 10.1021/ol200256a] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A study on the mechanism of the asymmetric intramolecular Stetter reaction is reported. This investigation includes the determination of the rate law, kinetic isotope effects, and competition experiments. The reaction was found to be first order in aldehyde and azolium catalyst or free carbene. A primary kinetic isotope effect was found for the proton of the aldehyde. Taken together with a series of competition experiments, these results suggest that proton transfer from the tetrahedral intermediate formed upon nucleophilic attack of the carbene onto the aldehyde is the first irreversible step.
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Affiliation(s)
| | - Anthony P. Silvestri
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | | | - Daniel A. DiRocco
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Tomislav Rovis
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
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191
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Guan XY, Wei Y, Shi M. Phosphane-Catalyzed Umpolung Addition Reaction of Nucleophiles to Ethyl 2-Methyl-2,3-butadienoate. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100095] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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192
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Cohen DT, Cardinal-David B, Scheidt KA. Lewis acid activated synthesis of highly substituted cyclopentanes by the N-heterocyclic carbene catalyzed addition of homoenolate equivalents to unsaturated ketoesters. Angew Chem Int Ed Engl 2011; 50:1678-82. [PMID: 21308931 PMCID: PMC3275665 DOI: 10.1002/anie.201005908] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 12/02/2010] [Indexed: 11/11/2022]
Affiliation(s)
- Daniel T Cohen
- Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Chemistry of Life Processes Institute, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
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193
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Vedachalam S, Wong QL, Maji B, Zeng J, Ma J, Liu XW. N-Heterocyclic Carbene Catalyzed Intramolecular Hydroacylation of Activated Alkynes: Synthesis of Chromones. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201000828] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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194
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Cohen DT, Cardinal-David B, Scheidt KA. Lewis Acid Activated Synthesis of Highly Substituted Cyclopentanes by the N-Heterocyclic Carbene Catalyzed Addition of Homoenolate Equivalents to Unsaturated Ketoesters. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201005908] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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195
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Fischer M, Schmölzer C, Nowikow C, Schmid W. Indium-Mediated Allenylation of Aldehydes and Its Application in Carbohydrate Chemistry: Efficient Synthesis of D-Ribulose and 1-Deoxy-D-ribulose. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001443] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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196
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Abstract
Organic chemistry is often considered a difficult subject requiring great effort to achieve expert status. Only once this level has been reached, judging, deciding, and recalling chemical information will be fast and guided by heuristic strategies. These principles, used intuitively, improve the efficiency and speed of problem-solving and decision-making procedures. Establishing these strategies in teaching and learning chemistry should significantly help students acquire well-structured procedural knowledge early in their education. In an attempt to improve conceptual thinking in teaching organic chemistry, in this contribution we develop a heuristic view of addition reactions and propose a new way of perceiving this class of organic reactions.
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Affiliation(s)
- Nicole Graulich
- Justus-Liebig-Universität Giessen, Institut für Organische Chemie, Heinrich-Buff-Ring 58, 35390 Giessen, Germany
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197
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Gliga A, Klare H, Schumacher M, Soki F, Neudörfl JM, Goldfuss B. New Umpolung Catalysts: Reactivity and Selectivity of Terpenol-Based Lithium Phosphonates in Enantioselective Benzoin-Type Couplings. European J Org Chem 2010. [DOI: 10.1002/ejoc.201001295] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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198
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Miyoshi T, Miyakawa T, Ueda M, Miyata O. Nucleophilic α-Arylation and α-Alkylation of Ketones by Polarity Inversion of N-Alkoxyenamines: Entry to the Umpolung Reaction at the α-Carbon Position of Carbonyl Compounds. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201004374] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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199
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