Dr Alan Kennedy

Publications

Synthesis of 2,6-trans-tetrahydropyrans using a palladium-catalyzed oxidative heck redox-relay strategy

Bonfield Holly E, Edge Colin M, Reid Marc, Kennedy Alan R, Pascoe David D, Lindsay David M, Valette Damien

Organic Letters Vol 26, pp. 2857-2861 (2024)

https://doi.org/10.1021/acs.orglett.3c03866

Modification of a common β-diketiminate NacNac framework via sequential lithiation and small molecule insertion

Lynch Jennifer R, Kennedy Alan R, Barker Jim, Mulvey Robert E

Chemistry - A European Journal Vol 30 (2024)

https://doi.org/10.1002/chem.202303373

Synthesis and reactivity of an aluminium n-heterocyclic aminal

Wilde Taylor, Murphy Fáinché, Smylie Cooper R T, Kennedy Alan R, Weetman Catherine E

Chemistry - An Asian Journal Vol 19 (2024)

https://doi.org/10.1002/asia.202301058

Isostructural behaviour in ammonium and potassium salt forms of sulfonated azo dyes

Kennedy Alan R, Kirkhouse Jennifer B A, McCarney Karen M, Puissegur Olivier

Acta Crystallographica Section C: Structural Chemistry Vol 80, pp. 66-79 (2024)

https://doi.org/10.1107/s2053229624001293

Isolable rubidium and caesium derivatives of common organic carbonyl compounds

Wacker Jakoba, Lynch Jennifer R, Banerjee Sumanta, MacDonald Peter A, Kennedy Alan R, Sarkar Biprajit, Mulvey Robert E

Chemical Communications Vol 60, pp. 91-94 (2024)

https://doi.org/10.1039/D3CC05527B

A structural comparison of salt forms of dopamine with the structures of other phenylethylamines

Kennedy Alan R, Cruickshank Laura, Maher Pamela, McKinnon Zoe

Acta Crystallographica Section C: Structural Chemistry Vol 79, pp. 386-394 (2023)

https://doi.org/10.1107/s2053229623007696

More publications

Teaching

Other Activities

I am also interested in public engagement in science and give a mean talk on scientific understanding, mis-understanding and downright stupidity.  Suitable for 15 to 90 year olds with or without a chemistry background.

Finally, we (of course) offer a commercial single crystal diffraction service to industry.  If you want to know more about this or any of the other activities above then feel free to get in touch. 

Research Interests

I work in a variety of areas, but it can all broadly be described as attempting to discover what materials’ structures can tell us about their chemical or physical properties.

As described in more detail below, my interests developed largely from early contacts with the work of Rab Mulvey (s-block metals), Ewen Smith (dyes and pigments) and the Solid-State group in what was Strathclyde's Pharmacy Dept. aka Alastair Florence and Norman Shankland (pharmaceutical materials).

So far this has led to around 600 publications - lately at a rate of about 24 per year.  Work has been sponsored by CNPq, GSK, AstraZeneca, Organon, Schering-Plough, the EPSRC, STFC, CCLRC, WESTChem and the University of Strathclyde.

s-Block Metals

Dyes and Pigments

The above work armed me with a newfound respect for all things alkaline – but also with a healthy distrust of systems that burst into flames every couple of days.  Whilst looking around for a simple (and water stable) application for knowledge of s-block structures I was introduced to dye and pigment chemistry by Prof. W. Ewen Smith.  Many so called organic colourants are in fact s-block metal complexes (indeed MOFs to the initiated).

We have shown that common sulphonated azo dyes have fascinating supramolecular structures ranging from solvent-seperated ion-pairs through simple chains, ladders and sheets to complex 3D networks. Building up a database of over 100 structures of simple salts of these dyes allows definitive predictions about their structures to be made - mostly based upon the metal cation used and the position of the sulfonate group.  This work has been extended to lake pigments, including a series of structures of Lithol Red.  This latter is of special interest due to its (mis?)use by the artist Rothko.  (See,  Chem. Eur. J. 2012, 18, 3064 & 2009, 15, 9494 &2004, 10, 4606; Inorg. Chem. 2006, 45, 2965; Angew. Chem. 2000, 112, 652; e-Preservation Sci. 2010, 7, 147. For work on other colourant systems see Chem. Commun. 2015, 51, 1143 and Cryst. Growth Des.,  2014, 14, 4849.)

The hope in this type of work is always that you can correlate structure to some useful physical property, but typically not enough structural information is available to make any useful predictions.

Now there is no excuse.  Modern crystallography, with fast diffractometers, synchrotron sources and structure solutions from powder diffraction data enables whole families of closely related structures to be elucidated, where previously only a few "important" compounds would be studied.

We've taken the approach of building structural databases of many related "boring" structures and gleaning information by studying patterns in the data as a whole as opposed to describing one structure at a time. (Mony a miekel maks a muckle, as my old granny would have said.  Ask your local Scottish person if you want a translation.)

This is what has allowed us to link simple characteristics of the metals (e.g. electronegativity) or dyes (e.g. SO₃ position) to solid-state structural type and this in turn is linked to properties of interest to manufacturers (solubility, morphology).

A similar methodology has allowed us to examine organic electronic materials, mostly BTBT-types (with Yves Geerts) and DPP-types (with Callum McHugh). Work published to date includes Adv. Mat. 2019, 1902407 & 2016, 28, 7106 & 2015, 27, 3066; ACS Appl. Mater. Interfaces 2015, 7, 1868; J. Mat. Chem. C 2016, 4, 7106; Cryst. Growth Des. 2016, 16, 2371.

Pharmaceutical Materials

We have also applied the mini-structural database idea that worked so well with dyes to pharmaceuticals.

The pharmacy industry calls this sort of thing salt-selection and they seem to have more money than the colourants chemists, so we've upped-sticks and jumped ship.  Special thanks must go here to AstraZeneca and Schering-Plough who initiated this mercenary behaviour.

It’s early as yet, but the structures are just as interesting, the links from structure to properties such as aqueous solubility, density and melting point are looking strong and I feel good about looking at socially useful materials.  Some aspects of this work can be seen in Cryst. Growth & Des. 2017, 17, 3277 & 2011, 11, 1318 & 1821.  See also Cryst. Growth & Des 2014 14, 6508 &  2013, 13, 5121 and Acta Cryst B 2012, 68, 453.

It would be nice to see some pretty colours again though, so any dye manufacturers with a few pounds to spare should feel free to call…

Professional Activities

Advising on chemicophysical materials

Advisor

1/2015

Glasgow Science Centre

Visiting researcher

2013

Expert Witness to the High Court (London)

Advisor

12/2011

ECCG4

Organiser

2011

Acta Crystallographica Section C: Crystal Structure Communications (Journal)

Editor

1/2011

3rd SCI Workshop on Practical Crystallisation

Chair

9/2010

More professional activities

Projects

Generating and Interrogating Crystallographic Data to Predict Solid-State Properties

Kennedy, Alan (Principal Investigator) Silva de Moraes, Lygia (Post Grad Student) Johnston, Blair (Co-investigator)

11-Jan-2015 - 01-Jan-2019

EXPLOITING SYNTHETIC AND STRUCTURAL SYNERGISM IN ALKALI-METAL-MEDIATED ORGANOTRANSITIONMETALLATION (AMMO)

Mulvey, Robert (Principal Investigator) Kennedy, Alan (Co-investigator)

The metallation reaction, where hydrogen is exchanged for a metal, is one of the most fundamental and important chemical transformations, being practised everyday in academic and industrial laboratories across the world. It is particularly useful in the manufacture of fine chemicals, pharmaceuticals, and polymers. Usually the metal employed in these reactions is lithium because of its high polarity and high reactivity. To attach a transition metal to carbon (aromatic) frameworks one would normally have to prepare the lithium derivative beforehand, then carry out a metal exchange reaction using a transition metal salt. This is necessary because transition metals are not generally reactive enough to be directly attached to an aromatic framework. However, there are limits to the usefulness of such exchange reactions due to solubility problems of the ionic salt in covalent organic solvents and to temperature sensitivities. This project will revolutionise this area as it will enable the development of the new concept of alkali-metal-mediated organotransitionmetallation (AMMO). Designing reagents containing an alkali metal and a transition metal within the same molecule, can lead to unique compounds that exhibit special synergic (mixed-metal) reactivities which cannot be replicated by alkali metal compounds or by transition metal compounds on their own (i.e. the single metal systems). Consequently using these two-metal based reagents, it is now possible to directly attach transition metal centres to aromatic frameworks. We have built prototype reagents based on lithium-manganese and sodium-manganese systems which can directly attach manganese to the carbon framework of the metallocene ferrocene, thus proving the concept. The innovative programme proposed will develop the synergic alkali metal chemistry of manganese with a range of other aromatic organic compounds and pioneer the same for other important transition metals including chromium, iron, cobalt and nickel. Incorporating transition metals with access to a large portfolio of properties (for example in redox chemistry, magnetochemistry and catalysis) within aromatic frameworks, will open up a treasure chest of new chemical opportunities outside the scope of conventional lithium-based aromatic compounds. The first transition metal host inverse crown macrocycles (special cyclic compounds with cationic host rings and anionic guest cores) will be prepared using AMMO. It is envisaged that, depending on the transition metal, some inverse crowns will exhibit interesting magnetic and material properties radically different to those of known inverse crowns which are based on magnesium and are therefore non-magnetic and non-redox active.

01-Jan-2008 - 31-Jan-2012

More projects