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A Coruña, Spain

Martinez-Ansemil E.,University da Corunna | Giacomazzi F.,Museo Civico di Storia Naturale | Sambugar B.,University da Corunna
Biologia (Poland) | Year: 2016

This work deals with the study of the oligochaete groundwater biodiversity in the Dinaric region, a karstic territory extending along the oriental shores of the Adriatic sea. Historical and new data depict a fauna of 123 species, 36 of which are stygobiotic. About 60% of the stygobionts are endemic to this region. Trichodrilus Claparède (Lumbriculidae) and Rhyacodrilus Bretscher (Rhyacodrilinae, Naididae) appear as highly diversified genera (13 and 10 species respectively); their diversification and radiative evolution in ground waters of the Dinaric region can be in relation with the fresh and stable temperatures in this environment, linked to isolate patches of karst. The presence of Parvidrilidae and Rhyacodriloidinae (Naididae) in this region is specially noteworthy; the parvidrilids are a groundwater Holarctic family present in Alabama (USA) and southern Europe and the rhyacodriloidines are a small Palaearctic group found in Lake Baikal and ground waters of the Limestone Alps (Italy) and the Dinaric karst of Slovenia and Croatia. The Phallodrilinae (Naididae) are represented in the Dinaric region by two species of Spiridion Knollner and two species of Abyssidrilus Erseus; both these genera seem to be representatives of two ways of colonization of continental ground waters, the former by migration through waters of decreasing salinity, and the later following the Regression model based on sea transgression and regression. Ground waters of the Dinaric region are confirmed as one of the most important hotspots of biodiversity in the world also for the oligochaete fauna. © 2016 Institute of Zoology, Slovak Academy of Sciences.

Fernandez A.,University da Corunna | Lopez-Torres M.,University da Corunna | Castro-Juiz S.,University da Corunna | Merino M.,University da Corunna | And 3 more authors.
Organometallics | Year: 2011

Reaction of the Schiff base ligand 1,4-[C(H)=N{9,10-(C8H 16O5)C6H3}]2C 6H4 (a), derived from terephthalaldehyde and 4′-aminobenzo-15-crown-5, with Pd(OAc)2 in chloroform at 50 °C for 96 h, gave the polymeric compound [Pd2{1,4-[C(H)=N{9,10- (C8H16O5)C6H3}] 2C6H2-C2,C5,N,N′}(μ-O 2CMe)2]n (1a) after double C-H activation at the C2 and C5 phenyl carbons. The metathesis reaction of 1a with saturated solutions of NtBu4Cl or NtBu4Br gave [Pd2{1,4-[C(H)=N{9,10-(C8H16O 5)C6H3}]2C6H 2-C2,C5,N,N′}(μ-Cl)2]n (2a) and [Pd2{1,4-[C(H)=N{9,10-(C8H16O 5)C6H3}]2C6H 2-C2,C5,N,N′}(μ-Br)2]n (3a), respectively, with exchange of the acetate group by a chloride or bromine ligand, also respectively, which likewise adopt polymeric arrangements. Further reaction of 2a with thallium acetylacetonate gave the dinuclear complex [Pd 2{1,4-[C(H)=N{9,10-(C8H16O5)C 6H3}]2C6H2-C2,C5,N, N′}{MeC(O)CH-C(O)Me-O,O′}2] (4a), whereas treatment of 2a with monophosphines in a 1:1 molar ratio resulted in splitting of the polymer and yielded the dinuclear complexes [Pd2{1,4-[C(H)=N{9,10-(C 8H16O5)C6H3}] 2C6H2-C2,C5,N,N′}(Cl)2(L) 2] (5a, L = PPh3; 6a, L = P(p-MeOC6H 4)3). The reactions of 2a with diphosphines were influenced by the length of the alkyl chain binding the two phosphorus atoms and the relative palladium atom/diphosphine molar ratio. Reaction of 2a with dppm in a 2:1 ratio gave the tetranuclear compound [{Pd2[1,4-{C(H)=N[9,10- (C8H16O5)C6H3]} 2C6H2-C2,C5,N,N′](Cl)2} 2(μ-Ph2PCH2P-Ph2)2] (7a) with the diphosphine in a bridging mode. However, treatment of 2a with dppm or dppe in a 1:1 ratio gave the dinuclear complexes [Pd2{1,4-[C(H)= N{9,10-(C8H16O5)C6H 3}]2C6H2-C2,C5,N,N′}(Ph 2PRPh2-P,P′)2][Cl]2 (8a, R = CH2; 9a, R = (CH2)2, respectively) with two chelating phosphines. With the longer chain diphosphines Ph2P(CH 2)nPPh2 (n = 4, dppb; n = 5, dpppe; n = 6, dpph) in a 1:1 palladium/diphosphine molar ratio the dinuclear compounds [Pd2{1,4-[C(H)=N{9,10-(C8H16O 5)C6H3}]2C6H 2-C2,C5}(Cl)2{μ-Ph2P(CH2) nPPh2}2] (10a, n = 4; 11a, n = 5; 12a, n = 6) were obtained, with two diphosphines intramolecularly bridging both palladium atoms. The molecular structures of compounds 5a, and 11a have been determined by X-ray diffraction analysis. © 2011 American Chemical Society.

Vazquez-Garcia D.,University da Corunna | Fernandez A.,University da Corunna | Lopez-Torres M.,University da Corunna | Rodriguez A.,University da Corunna | And 4 more authors.
Organometallics | Year: 2011

Reaction of 3,4-(C10H20O6)C 6H3C(Me)=NN(H)[3′-(CF3)C 4H2N2] (a) and 3,4-(C10H 20O6)C6H3C(Me)=NN(H)(4′- ClC4H2N2) (b) with Li2[PdCl 4] and sodium acetate in methanol at room temperature yielded the mononuclear cyclometalated complexes [Pd{3,4-(C10H20O 6)C6H2C(Me)=NN(H)[3′-(CF 3)C4H2N2]}(Cl)] (1a) and Pd{3,4-(C10H20O6)C6H 2C(Me)=NN(H)(4′-ClC4H2N 2)}(Cl)] (1b), respectively, with the ligand as terdentate [C,N,N]. The reaction of 1a and 1b with silver trifluoromethanesulfonate and triphenylphosphine yielded [Pd{3,4-(C10H20O 6)C6H2C(Me)=NN(H)[3′-(CF 3)C4H2N2]}(PPh3)][CF 3SO3] (2a) and [Pd{3,4-(C10H20O 6)C6H2C(Me)=NN(H)(4′-ClC 4H2N2)}(PPh3)][CF3SO 3] (2b) with the phosphine ligand occupying the vacant coordination position after chlorine abstraction; these were deprotonated at the hydrazine nitrogen after treatment with sodium acetate, yielding the [Pd{3,4-(C 10H20O6)C6H2C(Me)= NN[3′-(CF3)C4H2N2]}(PPh 3)] (3a) and [Pd{3,4-(C10H20O 6)C6H2C(Me)=NN(4′-ClC4H 2N2)}(PPh3)] (3b). Further treatment of 2b with silver trifluoromethanesulfonate gave 5b. Reaction of 2a and 2b with a Ag(I) salt and the tertiary diphosphine Ph2P(CH2) 4PPh2 (dppb) in 2:1 molar ratio gave the dinuclear complexes [{Pd{3,4-(C10H20O6)C 6H2C(Me)=NN(H)[3′-(CF3)C 4H2N2]}}2(μ-PPh 2(CH2)4PPh2)][CF3SO 3]2 (4a) and [{Pd[3,4-(C10H20O 6)C6H2C(Me)=NN(H)(4′-ClC 4H2N2)]}2((μ-PPh 2(CH2)4P-Ph2)][CF3SO 3]2 (4b) with the diphosphine as a bridging ligand. The crystal structures of complexes 1a and 5b are described, the latter crystallized with a Ag(I) atom complexed to the crown ether ring putting forward the ability of the complex to act as a metaloligand. © 2011 American Chemical Society.

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