Deciphering complexity in Pd-catalyzed cross-couplings.

Understanding complex reaction systems is critical in chemistry. While synthetic methods for selective formation of products are sought after, oftentimes it is the full reaction signature, i.e., complete profile of products/side-products, that informs mechanistic rationale and accelerates discovery chemistry. Here, we report a methodology using high-throughput experimentation and multivariate data analysis to examine the full signature of one of the most complicated chemical reactions catalyzed by palladium known in the chemical literature. A model Pd-catalyzed reaction was selected involving functionalization of 2-bromo-N-phenylbenzamide and multiple bond activation pathways. Principal component analysis, correspondence analysis and heatmaps with hierarchical clustering reveal the factors contributing to the variance in product distributions and show associations between solvents and reaction products. Using robust data from experiments performed with eight solvents, for four different reaction times at five different temperatures, we correlate side-products to a major dominant N-phenyl phenanthridinone product, and many other side products.

Selectivity of C-H Activation and Competition between C-H and C-F Bond Activation at Fluorocarbons.

Partially fluorinated alkanes, arenes, and alkenes can be transformed by a variety of transition metal and lanthanide systems. Although the C-H bond is weaker than the C-F bond regardless of the hybridization of the carbon, the reaction of the C-F bond at the metal is usually more exothermic than the corresponding reaction of the C-H bonds. Both bonds are activated by the metal systems, but the preference for activating these bonds depends on the nature of the hydrocarbon and of the metal system, so that the reaction can be directed exclusively toward C-H or C-F bonds or yield a mixture of products. Additionally, the presence of fluorine differentiates between C-H bonds at different positions resulting in regioselective C-H bond activation; paradoxically, the strongest C-H bond reacts preferentially. The purpose of this review is to describe the field of reactions of partially fluorinated substrates with transition metal atoms, ions, and molecular complexes. The controlling physical properties (thermodynamics and kinetics) are described first, followed by a description of stoichiometric reactions, with the competition between the C-H and C-F activations as focus. A few representative catalytic systems are discussed. The review also highlights the benefit of combining experimental and theoretical studies.

Redox-Tagged Carbon Monoxide-Releasing Molecules (CORMs): Ferrocene-Containing [Mn(C

This study describes the synthesis and characterization of a new class of ferrocene-containing carbon monoxide-releasing molecules (CORMs, 1-3). The ferrocenyl group is both a recognized therapeutically viable coligand and a handle for informative infrared spectroelectrochemistry. Deoxymyoglobin CO-release assays and in situ infrared spectroscopy confirm compounds 2 and 3 as photoCORMs and 1 as a thermal CORM, attributed to the increased sensitivity of the Mn-ferrocenyl bond to protonation in 1. Electrochemical and infrared spectroelectrochemical experiments confirm a single reversible redox couple associated with the ferrocenyl moiety with the Mn tetracarbonyl center showing no redox activity up to +590 mV vs Fc/Fc+, though no concomitant CO release was observed in association with the redox activity. The effects of linker length on communication between the Fe and Mn centers suggest that the incorporation of redox-active ligands into CORMs focuses on the first coordination sphere of the CORM. Redox-tagged CORMs could prove to be a useful mechanistic probe; our findings could be developed to use redox changes to trigger CO release.

Manganese(I)-Catalyzed C-H Activation: The Key Role of a 7-Membered Manganacycle in H-Transfer and Reductive Elimination.

Manganese-catalyzed C-H bond activation chemistry is emerging as a powerful and complementary method for molecular functionalization. A highly reactive seven-membered Mn(I) intermediate is detected and characterized that is effective for H-transfer or reductive elimination to deliver alkenylated or pyridinium products, respectively. The two pathways are determined at Mn(I) by judicious choice of an electron-deficient 2-pyrone substrate containing a 2-pyridyl directing group, which undergoes regioselective C-H bond activation, serving as a valuable system for probing the mechanistic features of Mn C-H bond activation chemistry.

Qualidade de vida e atividade física: um estudo correlacional em idosos com hipertensão arterial sistêmica / Quality of life and physical activity: a correlational study in elderly with systemic hypertension

O objetivo deste estudo foi investigar a relação entre qualidade de vida e o nível de atividade física de idosos com hipertensão arterial sistêmica da cidade de Mandaguaçu ­ PR. A amostra contou com 48 idosos de ambos os sexos com hipertensão arterial sistêmica, participantes do programa HIPERDIA. Como instrumentos foram utilizados o SF ­ 36, para analisar a qualidade de vida, e o IPAQ, para a mensuração do nível de atividade física. Para análise dos dados foram utilizados os testes "U" de Mann-Whitney, Kruskal Wallis e o Spearman (p≤0,05). Os idosos que obtiveram níveis altos de atividade física (83,3%) foram considerados ativos. Houve correlações significativas entre a qualidade de vida nas dimensões capacidade funcional, limitação por aspectos físicos e vitalidade com atividade física moderada e vigorosa. Ao final da pesquisa, foi possível concluir que quanto mais os idosos realizam atividades físicas moderadas e vigorosas, melhor é a qualidade de vida no aspecto da capacidade funcional.

The aim of this study was to investigate the relationship between the quality of life and the level of physical activity of elderly people with Systemic Arterial Hypertension in the city of Mandaguaçu - PR. The sample had 48 elderly people from both genders with hypertension. These people participated in the HIPERDIA program. The SF ­ 36 instrument was used to analyze the quality of life, and IPAQ for measuring the level of physical activity. For data analysis, the "U" Mann-Whitney, Kruskal Wallis and Spearman tests were used (p ≤ 0.05). The elderly who had high levels of physical activity (83.3%) were considered active. There were significant correlations between the quality of life in functional capacity, limitations on physical aspects and vitality aspects with moderate and vigorous physical activity. At the end of the research, it was possible to conclude that the more the participants practiced moderate and vigorous physical activities, the better it was for the quality of life in the functional capacity aspect.

A qualidade de vida no pré e pós-operatório de pacientes portadores de hérnia de disco lombar / The quality of life in pre and post surgical patients with lumbar disc herniation

A relevância dos estudos que abragem a hérnia de disco lombar (HDL) tem aumentado nos últimos anos, principalmente porque esta doença resulta em dor e déficit neurológico, gerando impedimento para a execução das atividades cotidianas e incapacidade para o trabalho. Objetivo: avaliar a qualidade de vida e o escore funcional de pacientesantes e após cirurgia de HDL. Casuística e Método: Trata-se de um estudo transversal, exploratório, mediante a avaliação dos questionários. "Short Form Health Survey" (SF-36) e "Roland-Morris"(RM) no período de abril a seyembro de 2008. A amostra foi composta 20 pacientes e os escores foram avaliados antes da cirurgia e no pós-operatório de dois meses de procedimentos. Resultados Observou-se que a maioria dos pacientes eram do sexo masculino (n=11, 55%), 45,5 ± 14,79 anos (variando de 20 a 83 anos), com grande prezuízo laboral pré cirurgia (60%). Os resultados demonstraram que houve melhora significativa nos domínios do SF-36 para capacidade funcional, aspectos físicos, dor e saúde mental e para Roland Morris foram observados ganhos funcionais com a diminuição de suas limitações provocadas pelas costas. Pela escala analógica de dor (EVA), os pacientes obtiveram uma diminuição importante do quadro álgico, pois no momento pré-cirúrgico obtiveram a média de 8,3 pontos e após 60 dias da cirurgia uma média 4,55. Ressalta-se que apesar de 65% dos pacientes retornarem ao trabalho, apenas 45% aderiram à reabilitação. Conclusão: Novos estudos devem ser realizados de maneira a oferecer subsídios à equipe multiprofissional mostrando que, mais do que abolir a dor, a melhora funcional expressa pelas atividades cotidianas, deve ser modificadas, sendo para isto necessário enfoque reabilitacional efetivo que inclua a terapia ocupacional, fisioterapia e psicologia, buscando operar mudanças e uma melhor qualidade de vida sempre.