Attention, working memory, and inhibitory control in aging: Comparing amateur singers, instrumentalists, and active controls.

Despite the ubiquity of musical activities, little is known about the specificity of their association with executive functions. In this cross-sectional study, we examined this relationship as a function of age. Our main hypotheses were that executive functions would decline in older age, that this relationship would be reduced in singers and instrumentalists compared to nonmusician active controls, and that the amount of musical experience would be more strongly associated with executive functions compared to the specific type of activity.

Nickel-Catalyzed Homologation of Vinylidene Difluoride (CH═CF): Selective β-F β-H Elimination.

Hydrofluoroolefins (HFOs) constitute the newest generation of fluorocarbon refrigerants and foam-blowing agents due to their reduced global warming potential their saturated analogues. To identify new synthetic routes to HFOs, we show that reactions of bulky Ni(0) phosphine and -NHC complexes with vinylidene difluoride (VF2) afford μ-fluoro-1,1,3-trifluorobut-3-enyl Ni complexes. Moreover, addition of triisopropylsilane allows for reductive elimination of the reduced product─2,4,4-trifluoro-1-butene─demonstrating the Ni-catalyzed hydrodefluorodimerization of VF2.

Fluorocarbon Refrigerants and their Syntheses: Past to Present.

This Review chronicles the progress made in the field of small fluorocarbon synthesis since their invention in the early 1930s by Thomas Midgley, Jr., and his coworkers, with special focus on their application as refrigerants, foam expansion agents, aerosol propellants, and precision solvents. Divided into four generations of C-C halocarbons from CFCs through HCFCs, HFCs, and HFOs, the merits and challenges of each will be discussed in the context of market demands, as well as the evolution of industrial manufacturing methods.

A T-shaped Ni[κ-(CF)-] NHC complex: unusual C -F and M-C bond functionalization reactions.

A T-shaped octafluoronickelacyclopentane-NHC complex is prepared and characterized. While the solid-state structure includes a weak isopropyl-CH agostic interaction, the reactivity of this complex with Lewis- and Brønsted acids is clearly enhanced by its low coordination number. Reaction with MeSiOTf, for example, yielded a rare metal-heptafluorocyclobutyl complex whereas carboxylic acids gave substitution at the α-carbon and/or Ni-C bond protonolysis to afford thermally robust 4-octafluorobutyl Ni complexes.