Browsing by Subject "Palladacycles"

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    C-H Activation in Primary 3-Phenylpropylamines: Synthesis of Seven-Membered Palladacycles through Orthometalation. Stoichiometric Preparation of Benzazepinones and Catalytic Synthesis of Ureas
    (ACS, 2016-06-06) Frutos-Pedreño, Roberto; García Sánchez, Eva; Oliva-Madrid, María José; Bautista, Delia; Martínez-Viviente, Eloísa; Saura-Llamas, Isabel; Vicente, José; Química Inorgánica
    The dimeric cyclometalated complexes [Pd2{C,N-C6H4CH2CH2C(R)(Me)NH2-2}2(µ-Cl)2] (R = Me (1a), H (1b)) are prepared by reacting 1,1-dimethyl-3-phenylpropylammonium or 1-methyl-3-phenylpropylammonium triflate with Pd(OAc)2 in a 1:1 molar ratio, and subsequent treatment with excess NaCl. The mononuclear derivatives [Pd{C,N-C6H4CH2CH2C(R)(Me)NH2-2}Cl(L)] (L = PPh3, R = Me (3a), H (3b); L = 4-picoline (4-pic), R = Me (4a), H (4b)) were prepared from 1a,b, by splitting the chloro-bridges with the neutral ligands L. A conformational analysis of the mononuclear palladacycles in solution has been carried out. Insertion of CO takes place into the Pd–C bond of complexes 1a,b affording Pd(0) and the tetrahydro-benzazepinone 5a or 5b, which possesses potential pharmacological interest. Additionally, the triflate salt A or B undergoes catalytic carbonylation with CO to afford the corresponding N,N’-dialkylurea, using Pd(OAc)2/Cu(OAc)2, in boiling acetonitrile. The crystal structures of 3a·1/2H2O, 3b, 4b·CHCl3, and 5a were determined by X-ray diffraction studies.
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    Ortho Palladation of the Phenethylamines of Biological Relevance L-Tyrosine Methyl Ester and Homoveratrylamine. Reactivity of the Palladacycles toward CO and Isocyanides. Synthesis of the Natural Alkaloid Corydaldine
    (ACS, 2012-05-14) Oliva-Madrid, María-José; García-López, José-Antonio; Saura-Llamas, Isabel; Bautista, Delia; Vicente, José; Química Inorgánica
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    Palladium-Mediated Functionalization of Benzofuran and Benzothiophene Cores
    (ACS, 2018-12-24) Pérez-Gómez, Marta; Hernández-Ponte, Sergio; García-López, José Antonio; Frutos-Pedreño, Roberto; Bautista, Delia; Saura-Llamas, Isabel; Vicente, José; Química Inorgánica
    The palladation reactions of 2-heteroaromatic primary phenethylamines bearing a benzofuran and benzothiophene nuclei have been studied. We have assessed the reactivity of the corresponding dimeric six-membered palladacycles (arising from C-H metalation) toward neutral ligands and unsaturated species. The insertion reactions of isocyanides into the Pd-C bond of the aforementioned palladacycles allowed the isolation of the corresponding iminoacyl intermediates, which could later be decomposed to give the amidine derivatives containing these relevant heterocyclic cores. In contrast, the carbonylation and alkenylation reactions led to straightforward formation of lactams and alkenylated organic derivatives. Interestingly, an unusual hydrogen-bond-promoted E-to-Z isomerization equilibrium of the resulting olefins was observed. Furthermore, we have studied the conditions to perform the alkenylation of the N-Boc derivatives of these substrates in a catalytic fashion. All the organometallic complexes (arising from the C-H activation of the heteroaromatic cores and insertion of isocyanides) and organic products (arising form the decomposition reactions) have been fully characterized, including the X-ray crystal structures of several organometallic and organic derivatives.