An anhydrous sol–gel system derived from methyldichlorosilane

Pyridine‐catalyzed reactions of methyldichlorosilane with bis(trimethylsilyl)carbodiimide afford a dichlorosilane‐derived anhydrous sol–­gel material. Both trimethylchlorosilane formation and Si–H disproportionation act as crosslinking mechanisms. The dried gels form amorphous or crystalline materials, depending on the sample history. The xerogels gave Si/C/N ceramics when pyrolyzed at 1200 °C. Copyright © 1999 John Wiley & Sons, Ltd.     

Safety as a Factor in Reaction Development: Considerations of Sensitization Potential with Amide Bond Forming Reagents

In response to an increased awareness of sensitization issues with amide bond forming agents, a detailed toxicological analysis of this broad family of reagents was undertaken which led to a quantitative ranking of the sensitization potential of these commonly used compounds. This data enables occupational toxicologists to guide the safer use of these reagents in the laboratory, but it also provides an opportunity for chemists working on reaction development, optimization and scale-up. To illustrate this, one of the strongest sensitizers, EDAC, is compared with the performance of one of the weakest, TCFH, showing the potential of this data for minimizing risks for researchers when using this family of reagents.