OrganoSulfur Chemistry

We are interested in developing new synthetic methods based on organosulfur chemistry.

Most recently, we have published an S-selective method for arylation of pyridylsulfides and shown how the resulting pyridylsulfonium salts can be used for the synthesis of 2,2’-, 2,3’, 2,4’-bipyridines (OL 2020 & 2021). This has generated a collaboration with the Draper group where we synthesised new bipyridine complexes with novel solvent dependent photophysical behaviour (ChemCommun 2023). We have also applied this in a synthesis of the caerulomycin family of natural products.

Org Lett 202022, 8451-8457. V K Duong, A M Horan, E M McGarrigle* Synthesis of Pyridylsulfonium Salts and Their Application in the Formation of Functionalized Bipyridines. DOI: 10.1021/acs.orglett.0c03048

Org Lett 202123, 9089-9093. A M Horan, V K Duong, E M McGarrigleSynthesis of Bis-heteroaryls Using Grignard Reagents and Pyridylsulfonium Salts. DOI:10.1021/acs.orglett.1c03379

Chem Commun 202359, 330-333. L Hallen, A Horan, B Twamley, E M McGarrigle,* S M Draper*Accessing unsymmetrical Ru(II) bipyridine complexes: a versatile synthetic mechanism for fine tuning photophysical properties. DOI: Abstract ja-2013-05073w_0001As part of a long-running project in the group of Prof Varinder Aggarwal FRS at the University of Bristol we have been involved in research on the development of chiral sulfur ylides for asymmetric epoxidation, aziridination and epoxidation. A major success story is the development of an easily accessible chiral sulfide which gives high enantioselectivities in epoxidations and aziridinations. isothiocineole TCIThe sulfide can be made from limonene and sulfur in just one step making it cheap to make. It has also become commercially available as a result of our work (TCI cat no T2578 & T2579; Aldrich 766429). We have described its synthesis and application on multi-gram scale.

See: J Am Chem Soc 2013, 135, 11951. DOI: 10.1021/ja405073w

J Am Chem Soc 2010, 132, 1828–1830. DOI: 10.1021/ja9100276

Synthesis 201850, 3337-3343. DOI: 10.1055/s-0037-1609580

We have also worked on improving mechanistic understanding of ylide reactions. Recently isotopic labelling studies revealed how an intramolecular proton transfer was hampering some asymmetric cyclopropanations.

JACS2010 Cycloprop GraphAbstract

See J Am Chem Soc 2010, 132, 7626–7630. DOI: 10.1021/ja910631u

In collaboration with Prof Varinder Aggarwal FRS, we have developed annulation reagents for synthesis of heterocycles that are of importance to the pharmaceutical industry (ACIE 2008 etc.). The parent reagent has been made commercially available for use by other scientists through Aldrich, and it has been used by many different pharmaceutical companies as evidenced by the peer-reviewed (e.g., ACIE 2010, 49, 3524; JOC 2010, 75, 7454; OPRD 2013, 17, 829) and patent literature (e.g., WO2009/153554; US/2012/0251497, WO/2010/014939; WO/2010/136778; US/2013/0017194; WO/2013/053051).

See Heterocycles section for more details.

Angew Chem Int Ed 200847, 3784–3786. M Yar, E M McGarrigle, V K Aggarwal* — ‘An Annulation Reaction for the Synthesis of Morpholines, Thiomorpholines and Piperazines from β-Heteroatom Amino Compounds and Vinyl Sulfonium Salts.’ DOI: 10.1002/anie.200800373

See the publications section for more published papers.