通过大学英语六级，并具有较强的英语口语能力。

By CET, and has strong English speaking skills.

Through a series of calorimetric studies, the research team observed that mixtures of NaH with either DMF or DMAc would begin to self-heat at temperatures as low as 26 °C and that the temperature would rapidly increase to 80 °C, at which point the cooling capacity of the pilot-plant reactor would be exceeded. They further commented that the onset temperature of decomposition was between 40 and 50 °C with carefully dried DMF; however, the detailed thermal stability data resulting from the study were not reported. A second account was reported by Burdick and Jackson Laboratories in the same year, stating that uncontrolled heating of a NaH/DMF reaction mixture began at 40 °C and that the reaction temperature quickly rose to more than 100 °C in less than 10 min.13 Although full cooling was applied to the reaction vessel, the temperature could not be controlled, and the majority of the DMF solvent evaporated before the reaction subsided. They commented that the reaction had been conducted many times without an incident, which highlights the unpredictable nature of this chemistry. While they suspected the reactor’s material of construction (stainless steel) to be the likely cause of the decomposition, this hypothesis was proven invalid by later studies and data presented in this contribution.<br>The safety concerns regarding the thermal instability of NaH mixtures were reiterated in two editorials by the previous Organic Process Research & Development Editor-in-Chief, Trevor Laird,14 who commented that multiple runaway reactions with NaH/DMF mixtures had occurred before the first report was published in 1982. These editorials drew much- needed attention to NaH-containing reactive mixtures and highlighted the importance of scientific communication to raise awareness of these hazards and alert others to such dangers.<br>Despite the numerous reports intended to caution scientists, the hazards associated with NaH/DMSO, NaH/DMF, and NaH/DMAc reactive mixtures remain underappreciated and inadequately discussed, overshadowed by the sheer number of publications that utilize these hazardous conditions, further diminishing their impact upon the chemistry community. As shown in Figures 1−3, the number of publications reporting the use of these hazardous conditions each year remains consistently high. Between 2014 and 2018, Organic Letters published 38−62 examples/year (Figure 1), whereas The Journal of Organic Chemistry (Figure 2) and the Journal of Medicinal Chemistry (Figure 3) published 28−46 and 67−94 examples/year, respectively.<br>It should be noted that most of the papers published in Organic Process Research & Development employing NaH/ DMSO, NaH/DMF, and NaH/DMAc only reported these hazardous conditions in their original discovery-phase routes (Figure 4). In most instances, the authors acknowledged the inherent safety hazards associated with these reactive mixtures and designed their processes away from these mixtures in the final routes. For example, Dahl et al.15 employed sodium dimsylate as the base in their process for the synthesis of (S)-2- ({3-[(S)-5-chloro-1-(4-chlorophenyl)indan-1-yl]propyl}- methylamino)propionic acid. The researchers performed a detailed reaction calorimetry evaluation, which indicated that the sodium dimsylate decomposed at temperatures as low as ∼50 °C with an adiabatic temperature rise (ΔTad) of 500 °C in pure DMSO. In contrast, when the DMSO solution of sodium dimsylate was diluted with THF, the lowest observed decomposition temperature was ∼100 °C with a ΔTad of 230 °C. On the basis of these results, the researchers ...

Pass CET-6, and have strong oral English ability.<br>