RESUMEN
Alkaline-earth metals have attracted increasing attention because they are cheap, Earth abundant and environmentally friendly, and have gradually become inexpensive and sustainable alternatives to traditional precious transition metal catalysts in many organic reactions. Recently, the hydroboration of unsaturated organic substrates has been extensively investigated. However, reports on alkaline-earth metal catalyzed hydroboration of isocyanates and ketones are rare. Herein, we report that simple, commercially available, and air-stable magnesium halides have been successfully employed as highly efficient catalysts in the hydroboration of isocyanates and ketones. Various boronate products were obtained in high yields with low catalyst loading under mild conditions.
RESUMEN
Two-dimensional (2D) black phosphorus (BP) has been reported to have appealing semiconducting properties as the sensing channel in field-effect transistor (FET) sensors. However, the intrinsic instability of BP in water greatly hinders its application, and little is known about its sensing performance and mechanism in aqueous medium. Herein, a water-stable BP FET sensor for antibiotic detection is reported. A novel surface engineering strategy with Ag+ coordination and melamine cyanurate (MC) supramolecular passivation is utilized to enhance the stability and transistor performance of BP. With molecularly imprinted polymers (MIPs) as the detection probe for tetracycline, the BPAg(+)/MC/MIPs sensor shows high sensitivity to tetracycline with a detection limit of 7.94 nM and a quick response within 6 s as well as high selectivity against other antibiotics with similar molecular structures. A new sensing mechanism relying on the conjugation effect of the probe structure is proposed, and new knowledge about alkalinity-enhanced and ionic strength-related response from the electrostatic gating effect is given based on the solution chemistry impact study. This work offers an efficient surface engineering strategy to enable the application of 2D BP for antibiotic detection in aqueous medium and presents a new sensing mechanism in chemical analysis by FET sensors.
Asunto(s)
Antibacterianos , Técnicas Biosensibles , Antibacterianos/química , Agua , Fósforo/química , TetraciclinasRESUMEN
A green and sustainable electrochemical hydroboration of carbonyl compounds with HBpin has been reported for the first time. Under catalyst-free and additive-free mild reaction conditions the corresponding boronic esters were obtained in excellent yields via the simple electrochemical hydroboration of various aldehydes and ketones with HBpin at room temperature. The scale-up reaction demonstrated potential practical applications. A plausible reaction mechanism was proposed based on the corresponding deuterium-labelling, radical inhibition and cyclic voltammetry experiments.