Publications

Heavy Atom Quantum Mechanical Tunneling in Total Synthesis Permalink

Published in Organic Letter, 2024

Contributions from quantum mechanical tunneling to the rates of several radical coupling reactions between carbon sp2 centers used as key steps in natural product total syntheses were computed using density functional theory. Contributions ranging from ∼15–52% from tunneling were predicted at room temperature, thereby indicating that tunneling plays an important role in the rates of these reactions and should perhaps be considered when designing complex synthetic schemes.

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Running Wild through Dirhodium Tetracarboxylate-Catalyzed Combined CH(C)-Functionalization/Cope Rearrangement Landscapes: Does Post-Transition-State Dynamic Mismatching Influence Product Distributions? Permalink

Published in Journal of the American Chemical Society 146 10, 2024

A special type of C–H functionalization can be achieved through C–H insertion combined with Cope rearrangement (CHCR) in the presence of dirhodium catalysts. This type of reaction was studied using density functional theory and ab initio molecular dynamics simulations, the results of which pointed to the dynamic origins of low yields observed in some experiments. These studies not only reveal intimate details of the complex reaction network underpinning CHCR reactions but also further cement the generality of the importance of nonstatistical dynamic effects in controlling Rh2L4-promoted reactions.

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Node-Aligned Graph-to-Graph: Elevating Template-free Deep Learning Approaches in Single-Step Retrosynthesis Permalink

Published in JACS AU 4 3, 2024

Deep learning techniques are increasingly used in single-step retrosynthesis prediction, but template-free models often struggle with atom alignment and ignore 2D molecular information, leading to lower performance compared to template-based methods. To address these issues, we introduce NAG2G, a transformer-based template-free model that combines 2D molecular graphs and 3D conformations, incorporates product-reactant atom mapping through node alignment, and demonstrates remarkable predictive accuracy.

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Analogies between photochemical reactions and ground-state post-transition-state bifurcations shed light on dynamical origins of selectivity Permalink

Published in Nature Chemistry, 2024

The origins of kinetic selectivity in organic chemistry can be revealed by comparing competing transition states, but in some cases, a single transition state leads to multiple products, and non-statistical dynamic effects influence selectivity control. Using machine-learning-assisted non-adiabatic molecular dynamics and multiconfiguration pair-density functional theory, we demonstrate that for the photochemical deazetization of 2,3-diazabicyclo[2.2.2]oct-2-ene, the momentum of the reacting molecules as they return to the ground state dominates the selectivity for hexadiene versus [2.2.2] bicyclohexane products, rather than the shape of the potential energy surfaces involved.

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Regiocontrol via Electronics: Insights into a Ru‐Catalyzed, Cu‐Mediated Site‐Selective Alkylation of Isoquinolones via a C− C Bond Activation of Cyclopropanols Permalink

Published in Chemistry–A European Journal 29 (55), e202301551, 2023

A Ru-catalyzed, Cu-mediated site-selective, C3/C4-alkylation of N-pyridylisoquinolones is achieved. The reaction pathway is characterized by open-shell singlet and triplet energy pathways arising from the bimetallic complex. Regioselectivity arises from the energies of the two states. While the electron-donating groups primarily afford the unprecedented C(4)-isomer, electron-withdrawing groups show an inclination towards the C(3)-product.

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NMR Prediction with Computational Chemistry Permalink

Published in Book: Enabling Tools and Techniques for Organic Synthesis: A Practical Guide to Experimentation, Automation, and Computation, 2023

This chapter reviews the typical procedures available for predicting and assigning structures using nuclear magnetic resonance (NMR) computations.

Novel D–A–D based near-infrared probes for the detection of β-amyloid and Tau fibrils in Alzheimer’s disease Permalink

Published in Chemical Communications 63, 2018

Novel D–π–A–π–D probes were investigated for the detection of Aβ plaques and NFTs. The probes displayed remarkable optical properties, and DADNIR-2 possessed high affinity towards Tau and Aβ aggregates (Kd = 0.41 nM and 1.04 nM, respectively) with certain selectivity. DADNIR-2 could penetrate the BBB and label Aβ plaques in vivo.

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