Abstract: The combination of a Pd(0) source and a phosphoramidite ligand promotes a formal allylic cross-coupling between alkylidenecyclopropanes (ACPs) and boronic acids to yield synthetically appealing 1,1-disubstituted alkenes. Remarkably, the reaction proceeds both under neutral and basic conditions, and works with both aryl- and alkenylboronic acids. DFT calculations suggest that the reaction entails a C-C activation/protonation mechanism instead of a hydropalladation pathway, such as has been proposed for other metal-promoted hydrofunctionalizations of ACPs.

External link: https://onlinelibrary.wiley.com/doi/abs/10.1002/adsc.202400657

We are so pleased to announce here that our last minireview at Angew. Chem. Int Ed., entitled "Bioorthogonal Synthetic Chemistry Enabled by Visible-Light Photocatalysis" and authored by M. Mato, X. Fernández-González, C. D'Avino, M. Tomás-Gamasa and J. L. Mascareñas, has been accepted and it's already on-line (gold Open Access).

Abstract: The field of bioorthogonal chemistry has revolutionized our ability to interrogate and manipulate biological systems at the molecular level. However, the range of chemical reactions that can operate efficiently in biological environments without interfering with the native cellular machinery, remains limited. In this context, the rapidly growing area of photocatalysis offers a promising avenue for developing new type of bioorthogonal tools. The inherent mildness, tunability, chemoselectivity, and external controllability of photocatalytic transformations make them particularly suitable for applications in biological and living systems. This minireview summarizes recent advances in bioorthogonal photocatalytic technologies, with a particular focus on their potential to enable the selective generation of designed products within biologically relevant or living settings.

External link: https://onlinelibrary.wiley.com/doi/10.1002/anie.202413506

Abstract: Low-valent cobalt complexes can promote intramolecular (3 + 2) cycloadditions of alkyne-tethered cyclopropenes to provide bicyclic systems containing highly substituted cyclopentadienyl moieties with electronically diverse functional groups. The adducts can be easily transformed into new types of CpRh(III) and CpIr(III) complexes, which show catalytic activity in several relevant transformations. Preliminary computational (DFT) and experimental studies provide relevant information on the mechanistic peculiarities of the cobalt-catalyzed process and allow us to rationalize its advantages over the homologous rhodium-promoted reaction.

External link: https://pubs.acs.org/doi/10.1021/acscatal.4c03080

We are so proud to announce here that our collaborative research article at JACS Au, entitled "De Novo Engineering of Pd-Metalloproteins and Their Use as Intracellular Catalysts" and authored by S. Learte-Aymamí, L. Martínez-Castro, C. González-González, M. Condeminas, P. Martin-Malpartida, M. Tomás-Gamasa, S. Baúlde, J. R. Couceiro, J.-D. Maréchal, M. J. Macias, J. L. Mascareñas and M. E. Vázquez, has been accepted and it's already on-line (gold Open Access) also being selected as "Editors' Choice".

Abstract: The development of transition metal-based catalytic platforms that promote bioorthogonal reactions inside living cells remains a major challenge in chemical biology. This is particularly true for palladium-based catalysts, which are very powerful in organic synthesis but perform poorly in the cellular environment, mainly due to their rapid deactivation. We now demonstrate that grafting Pd(II) complexes into engineered β-sheets of a model WW domain results in cell-compatible palladominiproteins that effectively catalyze depropargylation reactions inside HeLa cells. The concave shape of the WW domain β-sheet proved particularly suitable for accommodating the metal center and protecting it from rapid deactivation in the cellular environment. A thorough NMR and computational study confirmed the formation of the metal-stapled peptides and allowed us to propose a three-dimensional structure for this novel metalloprotein motif.

External link: https://pubs.acs.org/doi/10.1021/jacsau.4c00379