About

Nilay Hazari is the Chair and John Randolph Huffman Professor of Chemistry at Yale University. His research group focuses on synthetic inorganic and organometallic chemistry, emphasizing reaction mechanisms and catalysis. The long-term goal of his projects is to develop homogeneous transition metal catalysts for chemical transformations, aiming to create more energy-efficient and affordable industrial processes. His work involves understanding reaction mechanisms, which can play a crucial role in improving catalysts, using techniques such as multinuclear NMR spectroscopy, IR and UV-Visible spectroscopy, mass spectrometry, X-ray crystallography, isotopic labeling studies, and computational chemistry. Professor Hazari's research includes developing catalysts for the hydrogenation of carbon dioxide into formic acid and methanol, understanding reactions between carbon dioxide and transition metal complexes, designing molecular catalysts attached to semiconductors for photoreduction of carbon dioxide into liquid fuels, and exploring the role of Ni(I) complexes in organic transformations such as cross-coupling. His group also collaborates with researchers at Yale and other institutions to vary the properties of 2D materials using organic and organometallic molecules. His work supports efforts toward sustainable chemical processes and addressing climate change through innovative catalysis research.

Research topics

• Organic chemistry
• Chemistry
• Stereochemistry
• Physical chemistry
• Thermodynamics
• Computational chemistry
• Combinatorial chemistry
• Physics
• Medicinal chemistry

Selected publications

• Improving productivity and stability for CO2 hydrogenation by using pincer-ligated Mn complexes with hemilabile ligands

  Chem · 2026-01-05 · 1 citations

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• Photoelectrocatalytic reduction of CO2 to formate using immobilized molecular manganese catalysts on oxidized porous silicon

  UNC Libraries · 2026-03-10

  articleOpen access
  PublisherDOI

• A highly active sulfur based pincer ruthenium catalyst for CO₂ hydrogenation

  Chemical Communications · 2025-01-01 · 2 citations

  articleOpen access

  An air-stable SPS pincer ligand supports a highly active Ru catalyst for carbon dioxide hydrogenation.

  PublisherOA PDFDOI

• Flash Communication: Ir Complexes with a PhN(CH₂CH₂PⁱPr₂)₂ Pincer Ligand for Reversible CO₂ Hydrogenation

  Organometallics · 2025-06-21

  articleCorresponding

  The pincer ligand PhN(CH2CH2PiPr2)2 (iPrPNPhP) was treated with [Ir(coe)2(μ-Cl)]2 (coe = cyclooctene) under H2 to generate (iPrPNPhP)IrH2Cl (1). Reaction of 1 with LiBHEt3 formed (iPrPNPhP)IrH3 (2). The solid-state structures of 1 and 2 were determined. Compound 2 catalyzes CO2 hydrogenation to formate and formic acid dehydrogenation but gives inferior performance to systems with RN(CH2CH2PiPr2)2 (R = H or Me) ligands, demonstrating the importance of the substituent on the nitrogen donor.

  PublisherDOI

• Preface to Special Issue “Organometallic Chemistry of CO2”

  Journal of Organometallic Chemistry · 2025-04-03

  articleSenior authorCorresponding
  PublisherDOI

• Catalytic Hydrogenation of a Ruthenium Carbonyl to Formyl Enabled by Metal–Ligand Cooperation

  ACS Catalysis · 2025-07-22 · 1 citations

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  PublisherDOI

• Photoelectrocatalytic reduction of CO2 to formate using immobilized molecular manganese catalysts on oxidized porous silicon

  Open MIND · 2025-01-01

  article

• Elucidation of Marcus Relationships for Hydride Transfer Reactions Involving Transition Metal Hydrides

  Journal of the American Chemical Society · 2025-08-25 · 1 citations

  articleCorresponding

  The rate of hydride transfer from three Ir hydride complexes of the type Cp*Ir(Rbpy)H+ (Cp* = C5Me5; Rbpy = 4,4′-R-2,2′-bipyridine, R = OMe, H, CO2Me) to six N-methylacridinium (RAcr+) acceptors with electronically different substituents in the 2- or 2,7-positions were measured. Using the thermodynamic hydricity of the donors and the hydride affinity of the acceptors the thermodynamic driving forces for hydride transfer were determined. Brønsted plots, which correlate kinetic and thermodynamic hydricity, demonstrate distinct linear free energy relationships for each complex, with different Brønsted α values. Thus, at the same driving force hydride transfer from Cp*Ir(OMebpy)H+ is faster than for Cp*Ir(bpy)H+ or Cp*Ir(CO2Mebpy)H+. Experimental and computational analyses are consistent with a concerted hydride transfer mechanism for all Ir complexes. As the thermodynamic driving force increases an earlier transition state is observed and all transition states also include π-stacking interactions between the donor and acceptor, which likely contribute to the different α values. The experimental data fits well to the Marcus model, enabling the determination of reorganization energies (λ) that range from 58 to 69 kcal mol–1. These are lower than λ values for hydride transfer reactions involving organic donors and acceptors. This work provides a rare example of the correlation of kinetic and thermodynamic hydricity using only experimental data and shows that hydride transfer reactions involving metal hydrides can follow Marcus theory. The findings offer insight into controlling metal-catalyzed hydride transfer reactions, which is valuable for designing improved systems for a range of transformations.

  PublisherDOI

• Ni/Ti Dual Catalyzed Cross-Electrophile Coupling between Unactivated Alkyl Chlorides and Aryl Halides

  ACS Catalysis · 2025-06-23 · 6 citations

  articleCorresponding

  A dual Ni/Ti-catalyzed method for cross-electrophile coupling (XEC) of primary and secondary alkyl chlorides and aryl halides is described. This is a rare example of a thermal XEC reaction that directly couples unactivated alkyl chlorides, which are valuable substrates because of their accessibility and stability. Mechanistic studies indicate that the Ti catalyst, Cp*2TiIVCl2 (Cp* = pentamethyl-cyclopentadienyl), is crucial for activation of the alkyl chloride. Specifically, Cp*2TiIVCl2 undergoes reduction to form Cp*2TiIIICl, which was isolated and crystallographically characterized. Control experiments demonstrate that Cp*2TiIIICl reacts with primary, secondary, and tertiary alkyl chlorides to form alkyl radicals. While the Ni catalyst is not reactive enough to form alkyl radicals from alkyl chlorides directly, it is crucial for activating the aryl halide, resulting in the formation of an intermediate of the form (tBubpy)Ni(Ar)X (tBubpy = 4,4′-tBu2-2,2′-bipyridine; X = halide). Stoichiometric experiments showed that the (tBubpy)Ni(Ar)X intermediate captures alkyl radicals generated by the Ti catalyst and subsequently forms the organic XEC product. A key feature in the Ni/Ti dual catalyzed reaction is matching the rates of the Ni and Ti catalytic cycles, so that the rates of radical production and trapping are complementary. This can be achieved by varying the relative loadings of the Ni and Ti catalysts. It is expected that the strategy of using a second reactive catalyst to activate previously inert substrates in Ni-catalyzed XEC will be applicable to other challenging substrate classes.

  PublisherDOI

• Unusual Electrochemical Activity of Thin SiO ₂ Layers Leads to Instability of Molecular Attachment in Hybrid Photoelectrodes

  ACS Applied Energy Materials · 2025-12-01

  article

  Hybrid photoelectrodes, comprised of a light-absorbing semiconductor and a surface-integrated molecular catalyst, are attractive for applications in artificial photosynthesis, since they combine the advantages of broadband semiconductor light absorption with the selectivity of molecular catalysis. A widely used class of hybrid photoelectrodes is based on Si substrates passivated by a thin (<3 nm) layer of silicon oxide, which is commonly prepared by controlled chemical or thermal oxidation, resulting in chemical oxide (ChO) or thermal oxide (ThO) layers, respectively. However, the electrochemical stability of these oxide layers, and the chemical stability of the semiconductor-molecule assembly in hybrid photoelectrodes, are not well understood, with evidence that covalently bound molecules detach from the oxide surface upon application of cathodic bias. We have examined the intrinsic electrochemical reactivity of silicon oxide layers and how it affects the attachment of molecular monolayers. We determined that the surface of Si|ThO is primarily terminated with hydrophobic siloxane moieties, whereas that of Si|ChO contains a higher concentration of hydrophilic silanol groups. Initial high current densities for Si|ChO under applied bias up to −2 V vs Ag/AgCl, decrease during repeated cyclic voltammetry scans, due to the consumption of surface-bound water. This is manifested by a reversible wave around −0.5 V in CH3CN solution, and a similar pH-dependent wave in water, revealing the pKa of the silanol groups to be ∼4. Our combined observations support the electrochemically induced dehydration of the SiO2 surface, which converts silanol groups to siloxanes and proceeds through an H atom intermediate that is most likely stabilized by pentavalent Si. We propose that similar reactivity is responsible for the electrochemical loss of alkylsiloxane-attached molecules under cathodic bias, which has important implications for the choice of catalyst attachment strategy in hybrid photoelectrodes.

  PublisherDOI

Recent grants

• Mechanistic Studies to Rationally Design Ni and Pd Catalysts for Cross-Coupling

  NIH · $1.6M · 2016–2022

• Understanding the Reactions of Carbon Dioxide with Late Transition Metal Complexes

  NSF · $450k · 2020–2024

• CAREER: Mechanstic Studies Involving Late Transition Metal Complexes for Catalytic Carbon Dioxide Conversion

  NSF · $600k · 2012–2017

Frequent coauthors

• Brandon Q. Mercado

  Yale University

  133 shared

• Wesley H. Bernskoetter

  University of Missouri

  125 shared

• Louise M. Guard

  Eli Lilly (United States)

  86 shared

• Gary W. Brudvig

  Yale University

  65 shared

• Timothy J. Schmeier

  56 shared

• Michael K. Takase

  California Institute of Technology

  53 shared

• Ainara Nova

  University of Oslo

  52 shared

• David J. Charboneau

  Yale University

  47 shared

Awards & honors

• Rhodes Scholarship for New South Wales (2003)
• National Science Foundation Career Award (2012)
• Organometallics Fellow (from the American Chemical Society J…
• Alfred P. Sloan Research Fellow (2013)
• Camille and Henry Dreyfus Teacher-Scholar Award (2014)