Recent Research in Organic, Inorganic, Computational, and Medicinal Chemistry

Search for a Symmetrical C-F-C Fluoronium Ion in Solution: Kinetic Isotope Effects, Synthetic Labeling, and Computational, Solvent, and Rate Studies

Struble, M. D.; Holl, M. G.; Scerba, M. T.; Siegler, M. A.; Lectka, T. "Search for a Symmetrical C-F-C Fluoronium Ion in Solution: Kinetic Isotope Effects, Synthetic Labeling, and Computational, Solvent, and Rate Studies" J. Am. Chem. Soc. 2015, 137, 11476-11490

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Unstrained C-C Bond Activation and Directed Fluorination through Photocatalytically-Generated Radical Cations

Pitts, C. R.; Bloom, M. S.; Bume, D. D.; Zhang, Q. A.; Lectka, T. "Unstrained C-C Bond Activation and Directed Fluorination through Photocatalytically-Generated Radical Cations" Chem. Sci. 2015, 6, 5225-5229

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Site-Selective Approach to beta-Fluorination: Photocatalyzed Ring Opening of Cyclopropanols

Bloom, S.; Bume, D. D.; Pitts, C. R.; Lectka, T. "Site-Selective Approach to beta-Fluorination: Photocatalyzed Ring Opening of Cyclopropanols" Chem. Eur. J. 2015, 21, 8060-8063

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Synthesis of a Tight Intramolecular OH---Olefin Interaction, Probed by IR, 1H NMR, and Quantum Chemistry

Struble, M. D.; Holl, M. G.; Coombs, G.; Siegler, M. A.; Lectka, T. "Synthesis of a Tight Intramolecular OH---Olefin Interaction, Probed by IR, 1H NMR, and Quantum Chemistry" J. Org. Chem. 2015, 80, 4803-4807

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Direct NMR Detection of Bifurcated Hydrogen Bonding in the α-​Helix N-​Caps of Ankyrin Repeat Proteins

Preimesberger, M. R.; Majumdar, A.; Aksel, T.; Sforza, K.; Lectka, T.; Barrick, D.; Lecomte, J. T. J. "Direct NMR Detection of Bifurcated Hydrogen Bonding in the α-​Helix N-​Caps of Ankyrin Repeat Proteins" J. Am. Chem. Soc. 2015, 137, 1008-1011

 

Photocatalyzed Benzylic Fluorination: Shedding “Light” on the Involvement of Electron Transfer

Bloom, S.; McCann, M.; Lectka, T. "Photocatalyzed Benzylic Fluorination: Shedding “Light” on the Involvement of Electron Transfer" Org. Lett. 2014, 16, 6338-6341

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A Chelating Nucleophile Plays a Starring Role: 1,​8-​Naphthyridine-​Catalyzed Polycomponent alpha,​alpha-​Difluorination of Acid Chlorides

Griswold, A.; Bloom, S.; Lectka, T. "A Chelating Nucleophile Plays a Starring Role: 1,​8-​Naphthyridine-​Catalyzed Polycomponent alpha,​alpha-​Difluorination of Acid Chlorides" J. Org. Chem. 2014, 79, 9830-9834

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Triethylborane-​Initiated Radical Chain Fluorination: A Synthetic Method Derived from Mechanistic Insight

Pitts, C. R.; Ling, B.; Woltornist, R.; Liu, R.; Lectka, T. "Triethylborane-​Initiated Radical Chain Fluorination: A Synthetic Method Derived from Mechanistic Insight" J. Org. Chem. 2014, 79, 8895-8899

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A cooperative allylic fluorination: combination of nucleophilic and electrophilic fluorine sources

Bloom, S.; Knippel, J. L.; Holl, M. G.; Barber, R.; Lectka, T. "A cooperative allylic fluorination: combination of nucleophilic and electrophilic fluorine sources" Tetrahedron Lett. 2014, 55, 4576-4580

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Search for a Strong, Virtually "No-​Shift" Hydrogen Bond: A Cage Molecule with an Exceptional OH···F Interaction

Struble, M. D.; Kelly, C.; Siegler, M. A.; Lectka, T. "Search for a Strong, Virtually "No-​Shift" Hydrogen Bond: A Cage Molecule with an Exceptional OH···F Interaction" Angew. Chem. Int. Ed. 2014, 53, 8924-8928

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Direct, Catalytic Monofluorination of sp3 C-​H Bonds: A Radical-​Based Mechanism with Ionic Selectivity

Pitts, C. R.; Bloom, S.; Woltornist, R.; Auvenshine, D. J.; Ryzhkov, L. R.; Siegler, M. A.; Lectka, T. "Direct, Catalytic Monofluorination of sp3 C-​H Bonds: A Radical-​Based Mechanism with Ionic Selectivity" J. Am. Chem. Soc. 2014, 136, 9780-9791

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A photocatalyzed aliphatic fluorination

Bloom, S.; Knippel, J. L.; Lectka, T. "A photocatalyzed aliphatic fluorination" Chem. Sci. 2014, 5, 1175-1178

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Modulating "Jousting" C-​F-​-​-​H-​C Interactions with a Bit of Hydrogen Bonding

Struble, M. D.; Strull, J.; Patel, K.; Siegler, M. A.; Lectka, T. "Modulating "Jousting" C-​F-​-​-​H-​C Interactions with a Bit of Hydrogen Bonding" J. Org. Chem. 2014, 79, 1-6

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Metal-​Catalyzed Benzylic Fluorination as a Synthetic Equivalent to 1,​4-​Conjugate Addition of Fluoride

Bloom, S.; Sharber, S. A.; Holl, M. G.; Knippel, J. L.; Lectka, T. "Metal-​Catalyzed Benzylic Fluorination as a Synthetic Equivalent to 1,​4-​Conjugate Addition of Fluoride" J. Org. Chem. 2013, 78, 11082-11086

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Vibrational predissociation spectroscopy of Ar-tagged, trisubstituted silyl cations

DeBlase, A. F.; Scerba, M. T.; Lectka, T.; Johnson. M. A.   "Vibrational predissociation spectroscopy of Ar-tagged, trisubstituted silyl cations" Chem. Phys. Lett. 2013, in press

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Evidence for a Symmetrical Fluoronium Ion in Solution

Struble, M. D.; Scerba, M. T.; Siegler, M.; Lectka, T.   "Evidence for a Symmetrical Fluoronium Ion in Solution" Science 2013, 340, 57-60

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Iron(II)-Catalyzed Benzylic Fluorination

Bloom, S.; Pitts, C. R.; Woltornist, R.; Griswold, A.; Holl, M. G.; Lectka, T.   "Iron(II)-Catalyzed Benzylic Fluorination" Org. Lett. 2013, 15, 1722-1724

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A Polycomponent Metal-Catalyzed Aliphatic, Allylic, and Benzylic Fluorination

Bloom, S.; Pitts, C. R.; Miller, D.; Haselton, N.; Holl, M. G.; Urheim, E.; Lectka, T.   "A Polycomponent Metal-Catalyzed Aliphatic, Allylic, and Benzylic Fluorination" Angew. Chem. Int. Ed. Engl. 2012, 51, 1-5

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The Diels-Alder cyclization of ketenimines.

Erb, J.; Strull, J.; Miller, D.; He, J.; Lectka, T.  "The Diels–Alder Cyclization of Ketenimines" Org. Lett. 2012, 14(8), 2191-2193

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Characterization of highly unusual NH+-O hydrogen bonding to ester ether oxygen atoms through spectroscopic and computational studies.

Scerba, M. T.; DeBlase, A. F.; Bloom, S.; Dudding, T.; Johnson, M. A.; Lectka, T.  "Characterization of Highly Unusual NH+–O Hydrogen Bonding to Ester Ether Oxygen Atoms through Spectroscopic and Computational Studies" J. Phys. Chem. 2012, 116(14), 3556-3560

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Interaction of a C-F bond with the π-system of a C═C bond or "head on" with a proximate C-H bond.

Scerba, M. T.; Bloom, S.; Haselton, N.; Siegler, M.; Jaffe, J.; Lectka, T.  "Interaction of a C-F Bond with the pi-System of a C=C Bond or 'Head On' with a Proximate C-H Bond." J. Org. Chem. 2012, 77, 1605-1609

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NH+-F hydrogen bonding in a fluorinated "proton sponge" derivative: integration of solution, solid-state, gas-phase, and computational studies.

Scerba, M. T.; Leavitt, C. M.; Diener, M. E.; Deblase, A. F.; Guasco, T. L.; Siegler, M. A.; Bair, N.; Johnson, M. A.; Lectka, T.  "NH+-F Hydrogen Bonding in a Fluorinated "Proton Sponge" Derivative: Integration of Solution, Solid-State, Gas-Phase, and Computational Studies" J. Org. Chem. 2011, 76, 7975-7984

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Tricomponent Catalytic alpha,alpha-difluorination of Acid Chlorides

Bloom, S.; Scerba, M. T.; Erb, J.; Lectka, T.  "Tricomponent Catalytic alpha,alpha-difluorination of Acid Chlorides" Org. Lett. 2011, 13, 5068-5071

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From Bifunctional to Trifunctional (Tricomponent Nucleophile–Transition Metal–Lewis Acid) Catalysis: The Catalytic, Enantioselective alpha-Fluorination of Acid Chlorides

Erb, J.; Paull, D. H.; Belding, L.; Dudding, T.; Lectka, T.  "From Bifunctional to Trifunctional (Tricomponent Nucleophile–Transition Metal–Lewis Acid) Catalysis: The Catalytic, Enantioselective alpha-Fluorination of Acid Chlorides" J. Am. Chem. Soc. 2011, 133, 7536-7546

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Combining Asymmetric Catalysis with Natural Product Functionalization through Enantioselective alpha-Fluorination

Erb, J.; Alden-Danforth, E.; Kopf, N.; Scerba, M. T.; Lectka, T.  "Combining Asymmetric Catalysis with Natural Product Functionalization through Enantioselective alpha-Fluorination" J. Org. Chem. 2010, 75(3), 969-971

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Catalytic, Asymmetric Reactions of Ketenes and Ketene Enolates

Paull, D. H.; Weatherwax, A.; Lectka, T.  "Catalytic, Asymmetric Reactions of Ketenes and Ketene Enolates" Tetrahedron 2009, 65(34), 6771-6803

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Diastereoselective Synthesis of trans-beta-Lactams Using a Simple Multifunctional Catalyst

Abraham, C.; Paull, D. H.; Dogo-Isonagie, C.; Lectka, T.  "Diastereoselective Synthesis of trans-beta-Lactams Using a Simple Multifunctional Catalyst" Synlett 2009, 10, 1651-1654

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Catalytic, Asymmetric alpha-Fluorination of Acid Chlorides: Dual Metal-Ketene Enolate Activation

Paull, D. H.; Scerba, M. T.; Alden-Danforth, E.; Widger, L. R.;  Lectka, T.  "Catalytic, Asymmetric alpha-Fluorination of Acid Chlorides: Dual Metal-Ketene Enolate Activation" J. Am. Chem. Soc. 2008, 130(51), 17260-17261

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A Surprising Mechanistic 'Switch' in Lewis Acid Activation: A Bifunctional, Asymmetric Approach to alpha-Hydroxy Acid Derivatives

Abraham, C. J.; Paull, D. H.; Bekele, T.; Scerba, M. T.; Dudding, T; Lectka, T. "A Surprising Mechanistic 'Switch' in Lewis Acid Activation: A Bifunctional, Asymmetric Approach to alpha-Hydroxy Acid Derivatives" J. Am. Chem. Soc. 2008, 130(50), 17085-17094

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Asymmetric Cycloadditions of o-Quinone Methides Employing Chiral Ammonium Fluoride Precatalysts

Alden-Danforth, E.; Scerba, M. T.; Lectka, T. "Asymmetric Cycloadditions of o-Quinone Methides Employing Chiral Ammonium Fluoride Precatalysts" Org. Lett. 2008, 10(21), 4951-4953

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Bifunctional Asymmetric Catalysis: Cooperative Lewis Acid/Base Systems

Paull, D. H.; Abraham, C. J.; Scerba, M. T.; Alden-Danforth, E.; Lectka, T. "Bifunctional Asymmetric Catalysis: Cooperative Lewis Acid/Base Systems" Acc. Chem. Res. 2008, 41(5), 655-663

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An Asymmetric, Bifunctional Catalytic Approach to Non-Natural alpha-Amino Acid Derivatives

Paull, D. H.; Alden-Danforth, E.; Wolfer, J.; Dogo-Isonagie, C.; Abraham, C. J.; Lectka, T. "An Asymmetric, Bifunctional Catalytic Approach to Non-Natural alpha-Amino Acid Derivatives" J. Org. Chem. 2007, 72(14), 5380-5382

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Scalable Methodology for the Catalytic, Asymmetric alpha-Bromination of Acid Chlorides

Dogo-Isonagie, C.; Bekele, T.; France, S.; Wolfer, J.; Weatherwax, A.; Taggi, A. E.; Lectka, T. "Scalable Methodology for the Catalytic, Asymmetric alpha-Bromination of Acid Chlorides" J. Org. Chem. 2006, 71(23), 8946-8949

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Catalytic, Enantioselective Bifunctional Inverse Electron Demand Hetero-Diels--Alder Reactions of Ketene Enolates and o-Benzoquinone Diimides

Abraham, C. J.; Paull, D. H.; Scerba, M. T.; Grebinski, J. W.; Lectka, T. "Catalytic, Enantioselective Bifunctional Inverse Electron Demand Hetero-Diels--Alder Reactions of Ketene Enolates and o-Benzoquinone Diimides" J. Am. Chem. Soc. 2006, 128(41), 13370-13371

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