This Article describes the development of a stable Ni IV complex that mediates C(sp 2 )−H trifluoromethylation reactions. This reactivity is first demonstrated stoichiometrically and then successfully translated to a Ni IV -catalyzed C−H trifluoromethylation of electron-rich arene and heteroarene substrates. Both experimental and computational mechanistic studies support a radical chain pathway involving Ni IV , Ni III , and Ni II intermediates.

The development and application of a novel endo furan-protected maleimide building block is reported. The endo isomer undergoes deprotection at temperatures ~50 °C below the exo derivative. This enables a simple and powerful approach to quantitatively and selectively introduce functional maleimide groups via temperature modulation.

Herein, we report the development of a scalable and synthetically robust building block based on norbornadiene (NBD) that can be broadly incorporated into a variety of macromolecular architectures using traditional living polymerization techniques. By taking advantage of a selective and rapid deprotection with tetrazine, highly reactive "masked" cyclopentadiene (Cp) functionalities can be introduced into synthetic polymers as chain-end groups in a quantitative and efficient manner. The orthogonality of this platform further enables a cascade "click" process where the "unmasked" Cp can rapidly react with dienophiles, such as maleimides, through a conventional Diels−Alder reaction. Coupling proceeds with quantitative conversions allowing high molecular weight star and dendritic block copolymers to be prepared in a single step under ambient conditions.

A magnetically enhanced radio-frequency (rf) plasma source operating on water vapor has an extensive list of potential applications. In this work, the use of a rf plasma source to dissociate water vapor for hydrogen production is investigated. This paper describes a rf plasma source operated on water vapor and characterizes its plasma properties using a Langmuir probe, a residual gas analyzer, and a spectrometer. The plasma source operated first on argon and then on water vapor at operating pressures just over 300 mtorr. Argon and water vapor plasma number densities differ significantly. In the electropositive argon plasma, quasineutrality requires n(i) approximately = n(e), where n(i) is the positive ion density. But in the electronegative water plasma, quasineutrality requires n(i+) = n(i-) + n(e). The positive ion density and electron density of the water vapor plasma are approximately one and two orders of magnitude lower, respectively, than those of argon plasma. These results suggest that attachment and dissociative attachment are present in electronegative water vapor plasma. The electron temperature for this water vapor plasma source is between 1.5 and 4 eV. Without an applied axial magnetic field, hydrogen production increases linearly with rf power. With an axial magnetic field, hydrogen production jumps to a maximum value at 500 W and then saturates with rf power. The presence of the applied axial magnetic field is therefore shown to enhance hydrogen production.