Research Publications
Welcome to Day Lab's collection of research publications. This is the space where we share our latest findings and scientific contributions. Feel free to explore and delve into the details of our research work. For an updated and comprehensive list
Blueprints for the Geometric Control of N-Heterocyclic Carbene–Carbodiimide Isomers
This article presents the synthesis of a molecular framework capable of controlled and rational isomerization in 3D space. This system marks an advancement over conventional 2D building blocks, introducing an additional dimension of structural control and offering inspiration for innovative applications, either by expanding on the precedents set by their 2D counterparts or by exploring uncharted reticular frameworks.
Advances in understanding comproportionation and disproportionation in nickel catalysis
Disproportionation and comproportionation reactions have become routinely proposed events in modern synthetic endevours that use nickel catalysts. This new found appreciation from practitioners in the field for these electron transfer reactions has largely stemmed from our improved understanding of catalytic reactions. These studies have shown evidence of the ability of nickel complexes to occupy odd and even oxidation states which are critical to dictating reactivity. Comproportionation and disproportionation reactions shuttle nickel complexes between these oxidation states and are essential to the formation of either on-cycle or off-cycle species. This review will cover these fundamental reactions, and provide information about their role in catalysis.
Efficient palladium-catalyzed electrocarboxylation enables late-stage carbon isotope labelling
Carbon isotope labelling of bioactive molecules is essential for accessing the pharmacokinetic and pharmacodynamic properties of new drug entities. Aryl carboxylic acids represent an important class of structural motifs ubiquitous in pharmaceutically active molecules and are ideal targets for the installation of a radioactive tag employing isotopically labelled CO2. However, direct isotope incorporation via the reported catalytic reductive carboxylation (CRC) of aryl electrophiles relies on excess CO2, which is incompatible with carbon-14 isotope incorporation. Furthermore, the application of some CRC reactions for late-stage carboxylation is limited because of the low tolerance of molecular complexity by the catalysts. Herein, we report the development of a practical and affordable Pd-catalysed electrocarboxylation setup. This approach enables the use of near-stoichiometric 14CO2 generated from the primary carbon-14 source Ba14CO3, facilitating late-stage and single-step carbon-14 labelling of pharmaceuticals and representative precursors. The proposed isotope-labelling protocol holds significant promise for immediate impact on drug development programmes.
Kinetically-Controlled Ni-Catalyzed Direct Carboxylation of Unactivated Secondary Alkyl Bromides without Chain Walking
Herein, we report the direct carboxylation of unactivated secondary alkyl bromides enabled by the merger of photoredox and nickel catalysis, a previously inaccessible endeavor in the carboxylation arena. Site-selectivity is dictated by a kinetically controlled insertion of CO2 at the initial C(sp3)–Br site by the rapid formation of Ni(I)–alkyl species, thus avoiding undesired β-hydride elimination and chain-walking processes. Preliminary mechanistic experiments reveal the subtleties of stereoelectronic effects for guiding the reactivity and site-selectivity.