A reinvestigation into the chemical composition of potassium aminomethyltrifluoroborates is reported. These trifluoroborato salts have been reassigned as zwitterionic ammoniomethyltrifluoroborates. Minor adjustments to the previously disclosed reaction conditions are reported that permit a similar level of activity as nucleophiles in Suzuki–Miyaura cross-coupling reactions.

A new generation of borane−THF solutions stabilized with 0.005 M of 1,2,2,6,6-pentamethylpiperidine or N-isopropyl-N-methyl-tert-butylamine have been developed. These BTHF solutions show superior stability and reactivity at ambient temperatures when compared to BTHF complex unstabilized or stabilized with 0.005 M NaBH4.

Understanding the failure mechanisms of resin-coated proppants under extreme environments facilitates the development of stronger proppants for superior long-term performance in the oil and gas sector. In the current study, the leaching behavior of Novolac resin-coated proppants (RCPs) and that of polyurethane (PU) based RCPs with aqueous media under different pH conditions and at elevated temperatures have been critically examined, to assess their chemical stability and integrity. Our study indicates that Novolac-based RCPs are substantially more stable to leaching conditions at 250 8F compared to PU-based RCPs. An in-depth nuclear magnetic resonance analysis of the aqueous leachates from the RCP systems reveals that the averaged total levels of the leached components from the PU-based RCPs is five-to sevenfold higher than those of the Novolac RCPs at the higher temperature. In addition, a critical examination of the Novolac RCPs from a product safety and environmental health viewpoint is accomplished by ultraviolet-visible spectrophotometric analysis of the aqueous leachates. The findings reveal that the concentrations of the phenolics, including free phenol, are lower than the detectable limits (<1 ppm) of the technique. V C 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45845.

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