A Cu(II)-catalyzed ortho-selective functionalization of free phenols with trifluoroborates to afford C-C coupling products under mild conditions has been developed. A variety of functional groups on the phenol and the potassium aminomethyltrifluoroborate substrates were found compatible, furnishing the corresponding products in moderate to excellent yields. A single-electron transfer radical coupling mechanism involving a six-membered transition state is proposed to rationalize the high levels of ortho-selectivity in the reaction. This protocol provides straightforward access to ortho-aminomethyl-substituted phenols, unnatural amino acids and other bioactive small molecules.
Nanostructural catalyst with long-term durability under harsh conditions is very important for outstanding catalytic performance. Herein, a new ultra-stable PtCo/Co3O4-SiO2 nanocatalyst was explored to improve the catalytic performance of carbon monoxide (CO) oxidation in virtue of the active surface lattice oxygen derived from strong metal-support interactions. Such structure can overcome the issues of the Co3O4-SiO2 inactivation by water vapor and the Pt inferior activity at low temperature. Further, Co3O4-SiO2 nanosheets endow superior structure stability under a high temperature up to 800 °C, which gives the long-term catalytic cyclability of PtCo/Co3O4-SiO2 Table of Contents An ultra-stable PtCo/Co3O4-SiO2 nanocatalyst with active surface lattice oxygen have been explored to overcome the issues of Co3O4-SiO2 inactivation by water vapor and the Pt inferior activity at low temperature for catalyzing CO oxidation.
As a multigroup cross‐linking agent, amino acid derivatives contain different kinds of characteristic functional groups with different characteristics. Aiming at one of the most difficult problems, ionic defects, amino acid derivatives can passivate these defects through their multifunctional groups. Ionic defects (such as organic cations and halogen anions) mostly exist on surface and/or grain boundaries of perovskite films, and amino acid derivatives promote the formation of high‐quality perovskite films by coordinating well with these defects. Herein, the effects of two kinds of amino acids (l‐arginine and l‐glutamic acid) with contrastive isoelectric points (pIs) on perovskite film formation, defect passivation mechanism, device efficiency, flexible substrate, and thermal/moisture stability are studied. Efficiency of inverted perovskite solar cells is improved from ≈20% to nearly 23% with additives on rigid substrates. High pI l‐arginine improves the open‐circuit voltage significantly, while low pI l‐glutamic acid excels in fill factor and short‐circuit current. More importantly, low pI l‐glutamic acid shows superior thermal and moisture stability, indicating inherent stronger bonding between l‐glutamic acid and perovskite.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.