Search NASA⌕ Search
Home/Archive/DOE OSTI

DOE OSTI · 3377427

Direct Observation of Elusive (DTBM‐SEGPHOS)CuH Monomer Enables Mechanistic Insights Into Hydrocupration, Aggregation, and Dynamics of Alkene Functionalization Catalysis

Ryan, David E. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis]·Fuller, Jack T. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis]·Patrick, Evan A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis]·Erickson, Jeremy D. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000223351159)·Schenter, Greg K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000154445484)·Ginovska, Bojana [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000301658202)·Raugei, Simone [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000191188480)·Bullock, Ronald Morris [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000163064851)·Tran, Ba L. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000176613696)
View original source ↗Read source document ↗Export metadata ↓

Abstract

The bulky diphosphine DTBM-SEGPHOS is widely employed in CuH-catalyzed transformations as it provides remarkably active catalyst systems. The transient (DTBM-SEGPHOS)CuH monomer (LCuH) is the often-invoked active species. However, its instability has prevented spectroscopic characterization and mechanistic elucidation, hindering mechanistic understanding. We report low-temperature NMR spectroscopic characterization of LCuH, enabling quantitative kinetic analysis of the stoichiometric hydrocupration and catalytic hydroboration of cyclopentene, as well as the structural identification of two CuH clusters. LCuH inserts cyclopentene at −43°C, reaffirming its high reactivity toward olefins. LCuH deactivates to form L 2 Cu 3 H 3 and L 2 Cu 4 H 4 clusters, in which LCuH dimerization initiates aggregation. Kinetic analysis of reactions of unactivated alkenes indicates that competing on-cycle alkene hydrocupration and LCuH dimerization impact performance, as catalyst deactivation and turnover occur on comparable timescales. Structure–activity analysis using atomistic simulations shows that the steric profile of DTBM-SEGPHOS increases the CuH dimerization barrier by ∼7.7 kcal mol−1 compared to that of SEGPHOS, rationalizing the unique ability of DTBM-SEGPHOS to stabilize a reactive monomer for hydrocupration of broader alkene substrates. These findings illustrate the fundamental design principle that steric control of aggregation governs CuH catalyst performance, explaining both the exceptional activity of (DTBM-SEGPHOS)CuH and the limitations imposed by competing deactivation.

Explore related subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYaggregationcatalyst deactivationcopperhomogeneous catalysisreaction mechanisms

Keep this discovery

BibTeXRIS

Ryan, David E. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis], Fuller, Jack T. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis], Patrick, Evan A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis], Erickson, Jeremy D. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000223351159), Schenter, Greg K. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000154445484), Ginovska, Bojana [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000301658202), Raugei, Simone [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000191188480), Bullock, Ronald Morris [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000163064851), Tran, Ba L. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Institute for Integrated Catalysis] (ORCID:0000000176613696). 2026-07-10. Direct Observation of Elusive (DTBM‐SEGPHOS)CuH Monomer Enables Mechanistic Insights Into Hydrocupration, Aggregation, and Dynamics of Alkene Functionalization Catalysis. https://doi.org/10.1002/anov.70025

Cite the original work for its findings. Save a collection to share your selection of sources.

Discover connections

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY subject

Connections use source metadata and explicit phrase matches, not verified experimental comparisons.

KEEP EXPLORING

Related reports

DOE OSTI2023

Review of Carbon Support Coordination Environments for Single Metal Atom Electrocatalysts (SACS)

This topical review focuses on the distinct role of carbon support coordination environment of single-atom catalysts (SACs) for electrocatalysis. The article begins with an overview of atomic coordination configurations in SACs, including a discussion of the advanced characterization techniques and simulation used for understanding the active sites. A summary of key electrocatalysis applications is then provided. These processes are oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), nitrogen reduction reaction (NRR), and carbon dioxide reduction reaction (CO 2 RR). The review then shifts to modulation of the metal atom-carbon coordination environments, focusing on nitrogen and other non-metal coordination through modulation at the first coordination shell and modulation in the second and higher coordination shells. Representative case studies are provided, starting with the classic four-nitrogen-coordinated single metal atom (M$-$N 4 ) based SACs. Bimetallic coordination models including homo-paired and hetero-paired active sites are also discussed, being categorized as emerging approaches. The theme of the discussions is the correlation between synthesis methods for selective doping, the carbon structure–electron configuration changes associated with the doping, the analytical techniques used to ascertain these changes, and the resultant electrocatalysis performance. In conclusion, critical unanswered questions as well as promising underexplored research directions are identified.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Thermally Stable Co@C3N4 Single-Atom Catalysts for CO Oxidation: Atomic-Level Insights into Structure and Activity

Single Co atoms supported on C3N4 (Co@C3N4) have demonstrated high activity and selectivity in photocatalysis. However, the investigation of structure–function relationships and reaction mechanisms under photocatalytic conditions is very challenging due to the complex conditions of light absorption, charge transfer, and catalysis. In this study, we employed thermal CO oxidation as a prototypical probe reaction to benchmark the intrinsic catalytic performance and track the active-site evolution of Co@C3N4. Single Co atoms were identified and shown to be the catalytically active sites for CO oxidation based on control experiments and isotope-labeling experiments. The Co sites remained atomically dispersed before, during, and after the reaction with temperatures up to 400 °C, as established by in situ X-ray absorption fine structure (XAFS) combined with density functional theory (DFT), FDMNES simulations, and dynamic-time-warping (DTW)-assisted X-ray absorption near edge structure (XANES) matching. Together with theoretical calculations, the integrated analysis reveals a stable coordination environment under reaction conditions, which correlates with sustained activity, establishing Co@C3N4 single-atom catalysts as thermally stable CO oxidation catalysts. Beyond these findings, the current study provides a workflow for unambiguously assigning active sites in Co@C3N4 for thermal CO oxidation. This workflow will aid the understanding of their behavior in photocatalysis in the future, where light-driven dynamics obscure direct structure–function links. Notably, this study provides fundamental insights for the rational design of robust single-atom catalysts and a foundation for the broader application of Co@C3N4 catalysts in oxidation reactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Characterization of NBCMA—A DAPO Precursor

As part of our investigation into the process optimization of 2,6-diaminopyrazine-1-oxide (DAPO), small-scale sensitivity testing (impact, friction, and ESD) was conducted on the precursor, N-nitroso-bis(cyanomethyl)amine (NBCMA). NBCMA exhibited moderate sensitivity to friction, whereas no sensitivity to impact or spark was observed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗