Laurence Burroughs
University of Nottingham
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Laurence Burroughs.
Chemical Communications | 2010
Laurence Burroughs; Matthew E. Vale; James A. R. Gilks; Henrietta Forintos; Christopher J. Hayes; Paul A. Clarke
Esters of proteinogenic amino acids efficiently catalyse the formation of erythrose and threose under aqueous conditions in the highest yields and enantioselectivities yet reported. Remarkably while esters of (L)-proline yield (L)-carbohydrates, esters of (L)-leucine and (L)-alanine generate (D)-carbohydrates, offering the potential to account for the prebiotic link between natural (L)-amino acids and natural (D)-sugars.
Organic Letters | 2011
Paul A. Clarke; Soraia Santos; Nimesh Mistry; Laurence Burroughs; Alexander C. Humphries
The synthesis of the C1-C19 bis-pyran unit of phorboxazole B has been achieved. The key pyran rings were constructed by means of an asymmetric Maitland-Japp reaction and a second Maitland-Japp resolution/cyclization reaction. The longest linear sequence was 14 steps, and the C1-C19 bis-pyran unit was formed in an impressive 10.4% yield.
Advanced Materials | 2017
Florian Huewe; Alexander Steeger; Kalina Kostova; Laurence Burroughs; Irene Bauer; Peter Strohriegl; Vladimir Dimitrov; Simon Woodward; Jens Pflaum
Thermoelectric generator composed of crystalline radical ion salts: The unipolar charge transport along the molecular stacks facilitates complementary p- and n-type organic thermoelectric materials of high electrical conductivity and of 1D electronic structure. The specific power output of 5 mW cm-2 and the zT > 0.15 below 40 K demonstrate a new field of low-temperature thermoelectric applications unlocked by organic metals.
Chemistry: A European Journal | 2017
Simon Woodward; Miriam Ackermann; Saurabh K. Ahirwar; Laurence Burroughs; Mary Robert Garrett; John Ritchie; Jonathan Shine; Björk Tyril; Kevin Simpson; Peter Woodward
A simple regiospecific route to otherwise problematic substituted tetracenes is described. The diverse cores (E)-1,2-Ar1 CH2 (HOCH2 )C=C(CH2 OH)I (Ar1 =Ph, 4-MePh, 4-MeOPh, 4-FPh) and (E)-1,2-I(HOCH2 )C=C(CH2 OH)I, accessed from ultra-low cost HOCH2 C≡CCH2 OH at multi-gram scales, allow the synthesis of diol libraries (E)-1,2-Ar1 CH2 (HOCH2 )C=C(CH2 OH)CH2 Ar2 (Ar2 =Ph, 4-MePh, 4-iPrPh, 4-MeOPh, 4-FPh, 4-BrPh, 4-biphenyl, 4-styryl; 14 examples) by efficient Negishi coupling. Copper-catalysed aerobic oxidation cleanly provides dialdehydes (E)-1,2-Ar1 CH2 (CHO)C=C(CHO)CH2 Ar2 , which in many cases undergo titanium(IV) chloride-induced double Bradsher closure, providing a convenient method for the synthesis of regiochemically and analytically pure tetracenes (12 examples). The sequence is typically chromatography-free, scalable, efficient and technically simple to carry out.
Angewandte Chemie | 2015
Laurence Burroughs; Lee Eccleshare; John Ritchie; Omkar Kulkarni; Barry Lygo; Simon Woodward; William Lewis
An intramolecular Cannizzaro-type hydride transfer to an in situ prepared allene enables the synthesis of ortho-fused 4-substituted cycloocta-2,5-dien-1-ones with unprecedented technical ease for an eight-ring carboannulation. Various derivatives could be obtained from commercially available (hetero)aryl aldehydes, trimethylsilylacetylene, and simple propargyl chlorides in good yields.
Beilstein Journal of Organic Chemistry | 2015
Laurence Burroughs; John Ritchie; Mkhethwa Ngwenya; Dilfaraz Khan; William Lewis; Simon Woodward
Summary 1,4-Diols resulting from the double addition of ArCCLi (Ar = Ph, substituted phenyl, 2-thienyl) to ortho-C6H4(CHO)2 undergo cascades to tetracenes on simple admixture of LiHDMS, CS2 and MeI. Acene formation proceeds by [3,3]-sigmatropic rearrangement of xanthate anions followed by 6π electrocyclisations. The reactions are terminated by E2 or anionic Chugaev-type eliminations. Structural packing motifs and electronic properties are reported for the tetracenes.
Chemistry: A European Journal | 2016
Lee Eccleshare; Leticia Lozada‐Rodríguez; Phillippa Cooper; Laurence Burroughs; John Ritchie; William Lewis; Simon Woodward
Sequential treatment of 2-C6 H4 Br(CHO) with LiC≡CR(1) (R(1) =SiMe3 , tBu), nBuLi, CuBr⋅SMe2 and HC≡CCHClR(2) [R(2) =Ph, 4-CF3 Ph, 3-CNPh, 4-(MeO2 C)Ph] at -50 °C leads to formation of an intermediate carbanion (Z)-1,2-C6 H4 {CA (=O)C≡CB R(1) }{CH=CH(CH(-) )R(2) } (4). Low temperatures (-50 °C) favour attack at CB leading to kinetic formation of 6,8-bicycles containing non-classical C-carbanion enolates (5). Higher temperatures (-10 °C to ambient) and electron-deficient R(2) favour retro σ-bond C-C cleavage regenerating 4, which subsequently closes on CA providing 6,6-bicyclic alkoxides (6). Computational modelling (CBS-QB3) indicated that both pathways are viable and of similar energies. Reaction of 6 with H(+) gave 1,2-dihydronaphthalen-1-ols, or under dehydrating conditions, 2-aryl-1-alkynylnaphthlenes. Enolates 5 react in situ with: H2 O, D2 O, I2 , allylbromide, S2 Me2 , CO2 and lead to the expected C-E derivatives (E=H, D, I, allyl, SMe, CO2 H) in 49-64 % yield directly from intermediate 5. The parents (E=H; R(1) =SiMe3 , tBu; R(2) =Ph) are versatile starting materials for NaBH4 and Grignard C=O additions, desilylation (when R(1) =SiMe) and oxime formation. The latter allows formation of 6,9-bicyclics via Beckmann rearrangement. The 6,8-ring iodides are suitable Suzuki precursors for Pd-catalysed C-C coupling (81-87 %), whereas the carboxylic acids readily form amides under T3P® conditions (71-95 %).
ChemMedChem | 2018
Kathryn J. Skilling; Michael J. Stocks; Barrie Kellam; Marianne Ashford; Tracey D. Bradshaw; Laurence Burroughs; Maria Marlow
We have synthesized a range of gelators based on the nucleoside analogues gemcitabine and lamivudine, characterizing representative gels from the series using rheology and transmission electron microscopy. Growth inhibition studies of gemcitabine derivatives confirmed the feasibility of these compounds as novel treatments, indicating the potential of nucleoside‐based gelators for localized drug delivery.
Organic and Biomolecular Chemistry | 2012
Laurence Burroughs; Paul A. Clarke; Henrietta Forintos; James A. R. Gilks; Christopher J. Hayes; Matthew E. Vale; William Wade; Myriam Zbytniewski
ChemMedChem | 2018
Katherine J. Skilling; Michael J. Stocks; Barrie Kellam; Marianne Ashford; Tracey D. Bradshaw; Laurence Burroughs; Maria Marlow