Dr Anthony Haynes
Department of Chemistry
Reader in Inorganic Chemistry
+44 114 222 9326
Full contact details
Department of Chemistry
13 Brook Hill
Dr. Haynes obtained his BSc from the University of Exeter in 1986. After obtaining his PhD from the University of Nottingham in 1989, he became a BP Chemicals Research Fellow at the University of Sheffield until 1993, when he was appointed the BP Chemicals Lecturer in Homogeneous Catalysis.
In 1998 he was appointed as Lecturer at the University of Sheffield. From this post he was promoted to Senior Lecturer (2002) and Reader (2009).
- Research interests
The Haynes group investigates mechanistic aspects of homogeneous transition metal catalysed reactions, particularly industrially important processes such as methanol carbonylation and alkene hydroformylation. Synthetic, spectroscopic, kinetic and computational methods are used to study the structure and reactivity of organometallic complexes and their roles in catalysis.
Mechanisms of rhodium and iridium catalysed methanol carbonylation
The catalytic carbonylation of methanol to acetic acid is one of the most significant industrial applications of homogeneous transition metal catalysis. We have a long-standing research collaboration with BP Chemicals, who operate methanol carbonylation plants worldwide, and introduced a new process(Cativa TM) in 1995 that uses a promoted iridium/iodide catalyst. Highlights of our mechanistic studies include the first spectroscopic detection of a highly reactive Rh-methyl intermediate in the rhodium-catalysed process and elucidation of the role of promoters in the iridium-based system. We recently showed that the rate of migratory CO insertion in [Ir(CO)2I3Me]- is dramatically increased by isomerisation to place a CO ligand trans to methyl.
Ligand effects on oxidative addition and migratory CO insertion
We are interested in how the rates of key steps in catalytic cycles can be influenced by the electronic and steric properties of "spectator" ligands, e.g. phosphines, imines and N-heterocyclic carbenes. Strongly donating ligands tend to promote oxidative addition and retard migratory CO insertion, whereas sterically bulky ligands tend to have the opposite effects on these steps. In a recent study of the mechanism of rhodium/xantphos-catalysed methanol carbonylation it was found that the key intermediates contained xantphos coordinated as a tridentate "pincer" ligand and the nucleophilicity of the metal centre is enhanced by a Rh---O interaction.
Our experimental studies are complimented by theoretical calculations, carried out in collaboration with Dr. Anthony Meijer in this department. We are interested in modelling trends in organometallic reactivity and spectroscopic properties, e.g. vibrational spectra of metal carbonyl complexes.
The department is well-equipped with modern instrumentation for NMR spectroscopy, X-ray crystallography, mass-spectrometry and chromatography. In addition, the group has dedicated FTIR instruments for kinetic measurements, including high pressure and stopped-flow IR cells.
1. (a) JACS, 1991, 113, 8567; (b) JACS, 1993, 115, 4093.
2. JACS, 2004, 126, 2847.
3. Inorg. Chem., 2009, 48, 28
4. (a) JACS, 2002, 124, 13597; (b) Organometallics, 2003, 22, 1047; (c) Organometallics, 2003, 22, 4451.
5. Organometallics, 2011, 30, 6166.
- Mechanistic insight into organic and industrial transformations: general discussion. Faraday Discussions, 220, 282-316.
- Physical methods for mechanistic understanding: general discussion. Faraday Discussions, 220, 144-178.
- Encapsulation of Crabtree's Catalyst in Sulfonated MIL-101(Cr): Enhancement of Stability and Selectivity between Competing Reaction Pathways by the MOF Chemical Microenvironment. Angewandte Chemie, 130(17), 4622-4627.
- Encapsulation of Crabtree's Catalyst in Sulfonated MIL‐101(Cr): Enhancement of Stability and Selectivity between Competing Reaction Pathways by the MOF Chemical Microenvironment. Angewandte Chemie - International Edition, 57(17), 4532-4537. View this article in WRRO
- Infrared spectroscopic study of absorption and separation of CO using copper(I)-containing ionic liquids. Dalton Transactions, 46, 2821-2828. View this article in WRRO
- Encapsulation of an organometallic cationic catalyst by direct exchange into an anionic MOF. Chem. Sci., 7(3), 2037-2050. View this article in WRRO
- Reactivity of Ir(III) carbonyl complexes with water: alternative by-product formation pathways in catalytic methanol carbonylation. Dalton Transactions, 42(47), 16538-16546. View this article in WRRO
- Ligand effects on reactivity of cobalt acyl complexes. ACS Catalysis, 2(12), 2512-2523.
- Mechanistic study of rhodium/xantphos-catalyzed methanol carbonylation. Organometallics, 30(22), 6166-6179.
- Dicarbonylrhodium(I) complexes of bipyridine ligands with proximate H-bonding substituents and their application in methyl acetate carbonylation. European Journal of Inorganic Chemistry(23), 3511-3522.
- The structural characterization and hydroformylation activity of the tri-rhodium complex [Rh3(μ2-dppm)2(μ2-CO)3(κ1-CO)3]BF4. Inorganic Chemistry Communications, 12(10), 1071-1073.
- Iridium Complexes in Organic Synthesis.Edited by Luis A. Oro and Carmen Claver.. Angewandte Chemie International Edition, 48(33), 5993-5993.
- Identification of the reactive cis,mer isomer of [Ir(CO)2I3Me]-: relation to the mechanism of iridium-catalyzed methanol carbonylation.. Inorg Chem, 48(1), 28-35.
- Reactivity of rhodium(I) iminophosphine carbonyl complexes with methyl iodide. Organometallics, 26(8), 1960-1965.
- Ligand stereoelectronic effects in complexes of phospholanes, phosphinanes, and phosphepanes and their implications for hydroformylation catalysis. Organometallics, 26(3), 713-725.
- Formation and reactivity of Ir(III) hydroxycarbonyl complexes.. Inorg Chem, 45(16), 6269-6275.
- The synthesis, characterisation and reactivity of 2-phosphanylethylcyclopentadienyl complexes of cobalt, rhodium and iridium. Dalton Transactions(1), 91-107.
- Oxidative addition of MeI to cationic Rh(I) carbonyl complexes with pyridyl bis(carbene) ligands. Journal of Organometallic Chemistry, 690(24-25), 6089-6095.
- Facile alkene insertion into a rhodium(III)-acetyl bond: Potential catalysts for CO/alkene copolymerization. Organometallics, 23(25), 5907-5909.
- Iodide effects in transition metal catalyzed reactions.. Dalton Trans(21), 3409-3419.
- Kinetics and thermodynamics of C-Cl bond activation by [Ir(CO)2Cl2]-. Journal of Physical Organic Chemistry, 17(11), 1007-1016.
- Oxidative addition of methyl iodide to [Rh(CO)2I]2: synthesis, structure and reactivity of neutral rhodium acetyl complexes, [Rh(CO)(NCR)(COMe)I2]2. Inorganica Chimica Acta, 357(10), 3027-3037.
- Promotion of iridium-catalyzed methanol carbonylation: mechanistic studies of the cativa process.. J Am Chem Soc, 126(9), 2847-2861.
- Bis(imino)carbazolide complexes of rhodium: Highly nucleophilic ligands exerting a dramatic accelerating effect on MeI oxidative addition. Organometallics, 23(5), 1015-1023.
- Oxidative addition of MeI to a rhodium(I) N-heterocyclic carbene complex. A kinetic study. Organometallics, 22(22), 4451-4458.
- Mid-IR spectroscopy for rapid on-line analysis in heterogeneous catalyst testing. Catalysis Today, 81(3), 309-317.
- Quantifying steric effects of alpha-diimine ligands. Oxidative addition of MeI to rhodium(I) and migratory insertion in rhodium(III) complexes. Organometallics, 22(5), 1047-1054.
- Steric and electronic effects on the reactivity of Rh and Ir complexes containing P-S, P-P, and P-O ligands. Implications for the effects of chelate ligands in catalysis.. J Am Chem Soc, 124(45), 13597-13612.
- A mechanistic investigation of oxidative addition of methyl iodide to [Tp*Rh(CO)(L)]. Inorganic Chemistry, 41(12), 3280-3290.
- Structure and reactivity of polymer-supported carbonylation catalysts. J Chem Soc, Dalton Transactions(12), 2565-2572.
- Theoretical, thermodynamic, spectroscopic, and structural studies of the consequences of one-electron oxidation on the Fe-X bonds in 17-and 18-electron Cp*Fe(dppe)X complexes (X = F, Cl, Br, I, H, CH3). J Am Chem Soc, 123(41), 9984-10000.
- Two Metals are Better Than One. Education in Chemistry, 38(4), 99.
- Methane formation during the iridium/iodide catalysed carbonylation of methanol. Inorganic Chemistry Communications, 3(1), 11-12.
- A dramatic steric effect on the rate of migratory CO insertion on rhodium. J Am Chem Soc, 121(48), 11233-11234.
- The carbonylation of methyl iodide and methanol to methyl acetate catalysed by palladium and platinum iodides. Chemical Communications(2), 179-180.
- Spectroscopic identification and reactivity of [Ir(CO)3I2Me], a key reactive intermediate in iridium catalysed methanol carbonylation. Chemical Communications(9), 1023-1024.
- Model reactions of a carbonylation catalyst: phosphite induced migratory CO insertion in [MeIr(CO)2I3]-. Inorganica Chimica Acta, 270(1-2), 382-391.
- Cis-trans isomerism in [M(CO)2I4]- (M = Rh, Ir): Kinetic, mechanistic and spectroscopic studies. J Organomet Chem, 551(1-2), 339-347.
- Methyl to alkylidene migration within trans-[WMe(=CHPh)(CO)2(η-C5H5)]. Chemical Communications(15), 1765-1766.
- Methanol carbonylation revisited: Thirty years on. J Chem Soc Dalton Transactions(11), 2187-2196.
- Theoretical and experimental evidence for SN2 transition states in oxidative addition of methyl iodide to cis-[M(CO)2I2]- (M=Rh, Ir). J Am Chem Soc, 118(12), 3029-3030.
- The migratory insertion of carbon monoxide in pentamethylcyclopentadienyliridium(III) complexes. Structural effects on reactivity and mechanism for rhodium and iridium systems. Inorganica Chimica Acta, 240(1-2), 485-493.
- Dramatic Acceleration of Migratory Insertion in [Melr(CO)2I3]- by Methanol and by Tin(II) iodide. J Chem Soc Chemical Communications(10), 1045-1046.
- Oxidative Addition of Alkyl Halides to Rhodium(I) and Iridium(I) Dicarbonyl Diiodides: Key Reactions in the Catalytic Carbonylation of Alcohols. Organometallics, 13(8), 3215-3226.
- Mechanistic Studies on Rhodium Catalyzed Carbonylation Reactions: Spectroscopic Detection and Reactivity of a Key Intermediate, [MeRh(CO)2I3]-. J Am Chem Soc, 115(10), 4093-4100.
- Relative Reaction Rates for Rhodium and Iridium: Oxidative Addition of Methyl Iodide to M(I) and Migratory Insertion in M(III) Methyl Carbonyl Complexes. Gazzetta Chimica Italiana, 122(9), 391-393.
- Fe(CO)5 in CO cylinders. Chemistry in Britain, 28(6), 517-517.
- Direct Observation of MeRh(CO)2I3-, the Key Intermediate in Rhodium Catalyzed Methanol Carbonylation. J Am Chem Soc, 113(22), 8567-8569.
- A Mechanism for the Photochemical Conversion of FpSi2Me5 to FpSiMe3 (Fp = (η5-C5H5)Fe(CO)2). Infrared Evidence for an Intermediate Iron Silylene Complex. J Am Chem Soc, 113(6), 2011-2020.
- The Photochemistry of Dinuclear Osmium Carbonyl Complexes; Characterisation of Os2(CO)8 using Matrix Isolation. J Organomet Chem, 383(1-3), 497-519.
- rs-type Coordinates in Weakly Bonded Dimers: Application to Linear Dimers, B.....HCN, where B = CO, N2 and HCN. J Mol Struct, 189(1-2), 153-164.
- The Photochemistry of Cyclopentadienyl Platinum Carbonyl Dimers; Characterisation of [Pt2(µ-CO)(η5-C5R5)2] (R = H, Me) using Matrix Isolation and Fast Time-Resolved Infrared Spectroscopy. J Chem Soc Dalton Transactions(6), 1501-1507.
- Transition Metal Catalysed Methanol Carbonylation In Kamer PCJ, Vogt D & Thybaut JW (Ed.), Contemporary Catalysis: Science, Technology and Applications (pp. 795-822). London: RSC.
- Carbonylation Reactions In Reedijk J & Poeppelmeier K (Ed.), Comprehensive Inorganic Chemistry II: From Elements to Applications (pp. 1-24). Elsevier
- Catalytic Methanol Carbonylation In Gates BC & Knözinger H (Ed.), Advances in Catalysis (pp. 1-45).
- Commercial Applications of Iridium Complexes in Homogeneous Catalysis In Crabtree RH & Mingos DMP (Ed.), Comprehensive Organometallic Chemistry III (pp. 427-444). Elsevier
- Syntheses Based on Carbon Monoxide In Chiusoli GP & Maitlis PM (Ed.), Metal-catalysis in industrial organic processes (pp. 114-162). RSC
- Acetic acid synthesis by catalytic carbonylation of methanol In Beller M (Ed.), Catalytic Carbonylation Reactions (pp. 179-205).
- The Use of High Pressure Infrared Spectroscopy to Study Catalytic Mechanisms In Heaton B (Ed.), Mechanisms in Homogeneous Catalysis: A Spectroscopic Approach (pp. 107-150). Wiley VCH
- High throughput testing of catalysts for the hydrogenation of carbon monoxide to ethanol In Derouane EG, Parmon V, Lemos F & Ribeiro FR (Ed.), Principles and Methods for Accelerated Catalyst Design and Testing (pp. 299-303).
- Structure and reactivity of polymer-supported carbonylation catalysts In Sherrington DC & Kybett AP (Ed.), Supported Catalysts and their Applications (pp. 166-175).
- Chemical Marriage Brokers In Lister T (Ed.), Cutting edge chemistry (pp. 55-76). RSC
- Chemical Mariage Brokers In Hall N (Ed.), The Age of the Molecule (pp. 73-96). RSC
Conference proceedings papers
- Steric and electronic effects in the rhodium-catalyzed carbonylation reactions. Abstr Pap Am Chem Soc, Vol. 224 (pp U734-U734)
- Os2(CO)8, an apparent intermediate in the olefin and acetylene exchange-reactions of diosmacyclobutanes. Abstr Pap Am Chem Soc, Vol. 198 (pp 329-INOR)
- Teaching interests
Transition Metal Chemistry; Homogeneous Catalysis
- Teaching activities
Undergraduate and postgraduate taught modules
- Hydrogen and the s- and p-block elements (Level 1)
This segment introduces key concepts regarding the structures and properties of the s- and p-block elements.
- Reactivity and mechanisms of d-block complexes (Level 2)
This course describes and explains the reaction mechanisms of transition metal complexes.
- Organometallic Chemistry 1: longitudinal ligands (Level 3)
This segment deals with the synthesis, structure, bonding and reactivity of transition metal complexes containing metal-carbon σ-bonds. It introduces the role of these complexes in catalytic reactions.
- Homogeneous Catalysis (Level 4)
This course describes the chemical basis behind some economically important industrial processes which use homogeneous transition metal catalysts to manufacture important products such as solvents, pharmaceuticals, polymers and detergents.
- Tutorials: Level 1 General Chemistry.
- Tutorials: Level 2 Inorganic Chemistry.
- Skills for Success: Database Project.
- Level 3 Literature Review
- Level 4 Research Project
- Hydrogen and the s- and p-block elements (Level 1)