Search Results - "Johnston, Ryne C."

C-H···O non-classical hydrogen bonding in the stereomechanics of organic transformations: theory and recognition by Johnston, Ryne C, Cheong, Paul Ha-Yeon

“…This manuscript describes the role of non-classical hydrogen bonds (NCHBs), specifically C-HO interactions, in modern synthetic organic transformations. Our…”
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Direct visualization of critical hydrogen atoms in a pyridoxal 5′-phosphate enzyme by Dajnowicz, Steven, Johnston, Ryne C., Parks, Jerry M., Blakeley, Matthew P., Keen, David A., Weiss, Kevin L., Gerlits, Oksana, Kovalevsky, Andrey, Mueser, Timothy C.

“…Enzymes dependent on pyridoxal 5′-phosphate (PLP, the active form of vitamin B 6 ) perform a myriad of diverse chemical transformations. They promote various…”
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Formation of Aza-ortho-quinone Methides Under Room Temperature Conditions: Cs2CO3 Effect by Walden, Daniel M, Jaworski, Ashley A, Johnston, Ryne C, Hovey, M. Todd, Baker, Hannah V, Meyer, Matthew P, Scheidt, Karl A, Cheong, Paul Ha-Yeon

“…Since the first report of a facile, room temperature process to access aza-ortho-quinone methides (aoQMs) by Corey in 1999, this chemistry has remained dormant…”
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AlCl3‑Catalyzed Ring Expansion Cascades of Bicyclic Cyclobutenamides Involving Highly Strained Cis,Trans-Cycloheptadienone Intermediates by Wang, Xiao-Na, Krenske, Elizabeth H, Johnston, Ryne C, Houk, K. N, Hsung, Richard P

“…We report the first experimental evidence for the generation of highly strained cis,trans-cycloheptadienones by electrocyclic ring opening of 4,5-fused…”
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Torquoselective Ring Opening of Fused Cyclobutenamides: Evidence for a Cis,Trans-Cyclooctadienone Intermediate by Wang, Xiao-Na, Krenske, Elizabeth H, Johnston, Ryne C, Houk, K. N, Hsung, Richard P

“…Electrocyclic ring opening of 4,6-fused cyclobutenamides 1 under thermal conditions leads to cis,trans-cyclooctadienones 2-E,E as transient intermediates, en…”
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Mechanism and Stereoselectivity of a Dual Amino-Catalyzed Robinson Annulation: Rare Duumvirate Stereocontrol by Pierce, Matthew D, Johnston, Ryne C, Mahapatra, Subham, Yang, Hua, Carter, Rich G, Ha-Yeon Cheong, Paul

“…Computational study of the mechanisms and stereoselectivities of a dual amino-catalyzed synthesis of cyclohexenones containing all-carbon γ-quaternary and…”
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Mechanism and Stereocontrol: Enantioselective Addition of Pyrrole to Ketenes Using Planar-Chiral Organocatalysts by Pattawong, Ommidala, Mustard, Thomas J. L., Johnston, Ryne C., Cheong, Paul Ha-Yeon

“…In control: The computational study of the title reaction catalyzed by the planar‐chiral 4‐(pyrrolidino)pyridine is reported (see scheme). The resting state is…”
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Organocatalytic Kinetic Resolution Cascade Reactions: New Mechanistic and Stereochemical Manifold in Diphenyl Prolinol Silyl Ether Catalysis by McGarraugh, Patrick G., Johnston, Ryne C., Martínez-Muñoz, Aurora, Cheong, Paul Ha-Yeon, Brenner-Moyer, Stacey E.

“…A new cascade reaction involving an iminium‐catalyzed intramolecular oxa‐Michael addition followed by an enamine‐catalyzed intermolecular Michael addition is…”
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Catalyst selective and regiodivergent O- to C- or N-carboxyl transfer of pyrazolyl carbonates: synthetic and computational studies by Gould, Eoin, Walden, Daniel M, Kasten, Kevin, Johnston, Ryne C, Wu, Jiufeng, Slawin, Alexandra MZ, Mustard, Thomas JL, Johnston, Brittany, Davies, Tony, Ha-Yeon Cheong, Paul, Smith, Andrew D

“…The regiodivergent O- to C- or N-carboxyl transfer of pyrazolyl carbonates is described, with DMAP giving preferential N-carboxylation and triazolinylidenes…”
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Quantum Chemical Calculation of p Kas of Environmentally Relevant Functional Groups: Carboxylic Acids, Amines, and Thiols in Aqueous Solution by Lian, Peng, Johnston, Ryne C, Parks, Jerry M, Smith, Jeremy C

“…Developing accurate quantum chemical approaches for calculating p Kas is of broad interest. Useful accuracy can be obtained by using density functional theory…”
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Comment on the Definition and Labeling of pK50 by Watson, Mark A, Johnston, Ryne C, Bochevarov, Art

“…We propose a more rigorous definition for the recently introduced concept of pK50. The value of pK50 should be associated not with a "functional group", as…”
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Comment on the Definition and Labeling of p K 50 by Watson, Mark A, Johnston, Ryne C, Bochevarov, Art

“…We propose a more rigorous definition for the recently introduced concept of p . The value of p should be associated not with a "functional group", as…”
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Epik: pKa and Protonation State Prediction through Machine Learning by Johnston, Ryne C, Yao, Kun, Kaplan, Zachary, Chelliah, Monica, Leswing, Karl, Seekins, Sean, Watts, Shawn, Calkins, David, Elk, Jackson Chief, Jerome, Steven V, Repasky, Matthew P, Shelley, John C

“…Epik version 7 is a software program that uses machine learning for predicting the pKa values and protonation state distribution of complex, druglike…”
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Diastereo‐ and Enantioselective Construction of Stereochemical Arrays Exploiting Non‐Classical Hydrogen Bonding in Enolborates by Li, Matthew, Scheeff, Stephan, Chen, Jiahua, Johnston, Ryne C., Rizzo, Antonio, Krenske, Elizabeth H., Chiu, Pauline

“…We report a copper‐catalyzed reductive aldol addition to aldehydes and ketones, with pinacolborane as stoichiometric reductant, that results in the generation…”
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Computational Insights into the Central Role of Nonbonding Interactions in Modern Covalent Organocatalysis by Walden, Daniel M, Ogba, O. Maduka, Johnston, Ryne C, Cheong, Paul Ha-Yeon

“…The flexibility, complexity, and size of contemporary organocatalytic transformations pose interesting and powerful opportunities to computational and…”
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Catalytic Enantioselective [2,3]-Rearrangements of Allylic Ammonium Ylides: A Mechanistic and Computational Study by West, Thomas H, Walden, Daniel M, Taylor, James E, Brueckner, Alexander C, Johnston, Ryne C, Cheong, Paul Ha-Yeon, Lloyd-Jones, Guy C, Smith, Andrew D

“…A mechanistic study of the isothiourea-catalyzed enantioselective [2,3]-rearrangement of allylic ammonium ylides is described. Reaction kinetic analyses using…”
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Epik: p K a and Protonation State Prediction through Machine Learning by Johnston, Ryne C, Yao, Kun, Kaplan, Zachary, Chelliah, Monica, Leswing, Karl, Seekins, Sean, Watts, Shawn, Calkins, David, Chief Elk, Jackson, Jerome, Steven V, Repasky, Matthew P, Shelley, John C

“…Epik version 7 is a software program that uses machine learning for predicting the p values and protonation state distribution of complex, druglike molecules…”
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Mechanistic Investigation of Dimethylmercury Formation Mediated by a Sulfide Mineral Surface by Lian, Peng, Mou, Zhongyu, Cooper, Connor J, Johnston, Ryne C, Brooks, Scott C, Gu, Baohua, Govind, Niranjan, Jonsson, Sofi, Parks, Jerry M

“…Mercury (Hg) pollution is a global environmental problem. The abiotic formation of dimethylmercury (DMeHg) from monomethylmercury (MMeHg) may account for a…”
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Asymmetric Homoenolate Additions to Acyl Phosphonates through Rational Design of a Tailored N‑Heterocyclic Carbene Catalyst by Jang, Ki Po, Hutson, Gerri E, Johnston, Ryne C, McCusker, Elizabeth O, Cheong, Paul H.-Y, Scheidt, Karl A

“…A highly selective NHC-catalyzed synthesis of γ-butyro­lactones from the fusion of enals and α-keto­phosphonates has been developed. Computational modeling of…”
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Catalytic Kinetic Resolution of a Dynamic Racemate: Highly Stereoselective β-Lactone Formation by N -Heterocyclic Carbene Catalysis by Johnston, Ryne C, Cohen, Daniel T, Eichman, Chad C, Scheidt, Karl A, Cheong, Paul Ha-Yeon

“…This study describes the combined experimental and computational elucidation of the mechanism and origins of stereoselectivities in the NHC-catalyzed dynamic…”
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