A5026473752- Asymmetric Hydrogenation and Catalysis
- Asymmetric Synthesis and Catalysis
- Chemical Reactions and Isotopes
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Chemical Synthesis and Analysis
- Chemical Reaction Mechanisms
- Fluorine in Organic Chemistry
- Catalytic C–H Functionalization Methods
Binghamton University
2018-2022
β-Amino esters are obtained with high levels of enantioselectivity via the conjugate addition cyclic amines to unactivated α,β-unsaturated esters. A related strategy enables kinetic resolution racemic 2-arylamines, using benzyl acrylate as resolving agent. Reactions facilitated by an unprecedented selenourea-thiourea organocatalyst. As elucidated DFT calculations and 13C isotope effect studies, rate-limiting enantiodetermining step reaction is protonation a zwitterionic intermediate...
Experimental 13C kinetic isotope effects (KIEs) and density functional theory (DFT) calculations are used to evaluate the mechanism origin of enantioselectivity in formal C(sp2)–H alkylative desymmetrization cyclopentene-1,3-diones using nitroalkanes as alkylating agent. An unusual combination an inverse (∼0.980) a normal (∼1.033) KIE is observed on bond-forming carbon atoms cyclopentene-1,3-dione nitroalkane, respectively. These data provide strong support for involving reversible...
Abstract A combination of experimental 13 C kinetic isotope effects (KIEs) and high‐level density functional theory (DFT) calculations is used to distinguish between “enamine” “enol” mechanisms in the Michael addition acetone trans ‐β‐nitrostyrene catalyzed by Jacobsen's primary amine thiourea catalyst. In light recent findings that widely 18 O‐incorporation probe for these flawed, results described this communication demonstrate an alternative pathways. key advantage quantitative...
ABSTRACT: Experimental 13C kinetic isotope effects (KIEs) and DFT calculations are used to evaluate the mecha-nism origin of enantioselectivity in C(sp2)‒H alkylative desymmetrization cyclopentene-1,3-diones using nitroalkanes as alkylating agent. An unusual combination an inverse (~0.980) a normal (~1.030) KIE is observed on bond-forming carbon atoms cyclopentene-1,3-dione nitroalkane, respectively. These data provide strong support for mechanism involving reversible carbon-carbon...
ABSTRACT: Experimental 13C kinetic isotope effects (KIEs) and DFT calculations are used to evaluate the mecha-nism origin of enantioselectivity in C(sp2)‒H alkylative desymmetrization cyclopentene-1,3-diones using nitroalkanes as alkylating agent. An unusual combination an inverse (~0.980) a normal (~1.030) KIE is observed on bond-forming carbon atoms cyclopentene-1,3-dione nitroalkane, respectively. These data provide strong support for mechanism involving reversible carbon-carbon...