2026-04-14T05:35:24Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1417402025-12-04T21:44:43Zcom_2072_1057col_2072_478917col_2072_478933

Synthesis, characterization, solution behavior and theoretical studies of Pd(II) Allyl Complexes with 2-Phenyl-3H-indoles as ligands Tomé, Maria Grabulosa, Arnald Rocamora, Mercè Aullón López, Gabriel Font Bardia, Ma. Mercedes Calvet Pallàs, Maria Teresa López Martínez, Ma. Concepción Catàlisi homogènia Lligands Compostos orgànics Homogeneous catalysis Ligands Organic compounds The study of the reactivity of three 2-phenyl-3H-indole ligands of general formulae C8H3N-2-(C6H4-4-R1)-3-NOMe-5-R2 (1) [with R1 = H, R2 = OMe (a); R1 = R2 = H (b) or R1 = Cl, R2 = H (c)] with [Pd(η3-1-R3C3H4)(μ-Cl)]2 (R3 = H or Ph) has allowed us to isolate two sets of new Pd(II)-allyl complexes of general formulae [Pd(η3-1-R3C3H4)(1)Cl] {R3 = H (2) or Ph (3)}. Compounds 2a-2c and 3a-3c were characterized by elemental analyses, mass spectrometry and IR spectroscopy. The crystal structures of 2a, 3a and 3b were also determined by X-ray diffraction. 1H-NMR studies reveal the coexistence of two (for 2a-2c) or three (for 3a-3c) isomeric forms in CD2Cl2 solutions at 182 K. Additional studies on the catalytic activity of mixtures containing [Pd(η3-C3H5)(μ-Cl)]2 and the parent ligand (1a-1c) in the allylic alkylation of (E)-3-phenyl-2-propenyl (cinnamyl) acetate with sodium diethyl 2-methylmalonate as well as the stoichiometric reaction between compounds 3a and 3c with the nucleophile reveal that in both cases the formation of the linear trans- derivative is strongly preferred over the branched product. Computational studies at a DFT level on compound 3a allowed us to compare the relative stability of their isomeric forms present in solution and to explain the regioselectivity of the catalytic and stoichiometric processes. 2019-10-04T17:15:44Z 2019-10-04T17:15:44Z 2019-09-27 2019-10-04T17:15:44Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2073-4344 https://hdl.handle.net/2445/141740 691796 eng Reproducció del document publicat a: https://doi.org/10.3390/catal9100811 Catalysts, 2019, vol. 9, num. 10, p. 811 https://doi.org/10.3390/catal9100811 cc-by (c) Tomé, Maria et al., 2019 http://creativecommons.org/licenses/by/3.0/es info:eu-repo/semantics/openAccess application/pdf MDPI Articles publicats en revistes (Química Inorgànica i Orgànica)