Manejo tradicional de plantas em regiões neotropicais Traditional management of plants in the Neotropical region

É apresentada breve revisão sobre os principais aspectos do manejo tradicional de plantas exercidos nas regiões neotropicais, tendo como objetivos: 1. descrever como algumas populações tradicionais manejam seus recursos vegetais; 2. identificar as principais estratégias empregadas; 3. ressaltar a contribuição desse conhecimento para o desenvolvimento sustentável e manejo de recursos vegetais. São caracterizados e discutidos dois tipos de manipulação dos recursos vegetais: o de comunidade e o de espécies individuais. É possível verificar que os sistemas de conhecimento tradicional podem contribuir para o desenvolvimento sustentável, visto que algumas populações locais manejam as plantas com base em concepção sistêmica do ambiente e atitude de profunda reverência para com a natureza.<br>The main aspects of traditional plant management techniques exercised in the Neotropic are briefly reviewed. The aims of this work are: 1. to describe how some traditional populations, especially those located in Neotropical areas, manage natural resources; 2. to identify the main strategies employed; 3. to emphasize the contribution of traditional techniques to the sustainable development and management of natural resources. Two types of resource management are characterized and discussed: community management, and individual species management. In view of the fact that some traditional populations manage natural resources based on an integrated conception of nature, it is possible to verify that traditional knowledge systems can contribute to sustainable development

Unprecedented addition of tetrahydroborate to an osmium-carbon triple bond

The complexes [OsHCl(≡CPh)(IPr)(PR3)]OTf (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolylidene; OTf = CF3SO 3; PR3 = PiPr3 (1), PPh3 (2)) react with NaBH4 in tetrahydrofuran to give OsH 2Cl(η2-H-BCH2Ph)(IPr)(PR3) (PR3 = PiPr3 (3), PPh3 (4)). The mechanism of addition has been studied by means of isotopic labeling experiments and DFT calculations. The results indicate that the boron ligand is generated by hydroboration of the Os≡C triple bond of 1 and 2 and subsequent B-H bond activation of the resulting alkylborane. The original hydride ligand does not participate in the hydroboration process. However, it plays a secondary role in the B-H bond activation. © 2014 American Chemical Society.Financial support from the Spanish MINECO (Projects CTQ2011-23459, CTQ2010-20714-C02-01/BQU) and Consolider Ingenio 2010 (CSD2007-00006), the DGA (E35), and the European Social Fund (FSE) is acknowledged. J.J.F.C. acknowledges support via a predoctoral fellowship from the DGA.Peer Reviewe

Synthesis and Structural Characterization of Ruthenium Carbonyl Cluster Complexes Containing Platinum with a Bulky N-Heterocyclic Carbene Ligand

The reaction of Ru3(CO)12 with Pt(IMes)2 in benzene solvent at room temperature afforded the monoplatinum-triruthenium cluster complex Ru3Pt(IMes)2(CO)11, 1, in 21% yield and the trigonal bipyramidal cluster complex Ru3Pt2(IMes)2(CO)12, 2, in 26% yield. The reaction of Ru(CO)5 with Pt(IMes)2 in benzene solvent at 0 °C yielded two trinuclear cluster complexes, the monoplatinum-diruthenium Ru2Pt(IMes)(CO)9, 3, and the monoruthenium-diplatinum cluster complex RuPt2(IMes)2(CO)6, 4. The reaction of 2 with hydrogen at 80 °C afforded the tetrahydrido-tetraruthenium complex Ru4(IMes)(CO)11(μ-H)4, 5, and the dihydrido-diruthenium-diplatinum complex Ru2Pt2(IMes)2(CO)8(μ-H)2, 6. All six compounds were structurally characterized by single-crystal X-ray diffraction analyses