Synthesis of Heterocycles

摘要: The synthesis of carbamates and isocyanates via the catalytic carbonylation organic nitro compounds (Chapters 2 3) is still not competitive with respect to classical phosgene route. However, this true if we consider only cost reagents complexity equipment required by two alternative routes. We are now living in a time which environmentally friendly processes and, when evaluating routes product, both amount nature waste make difference [1]. Moreover, chlorine-based chemistry currently under fire from those concerned about its potential environmental impact [2]. When chlorine reagent does appear an route becoming highly desirable. Anyhow, being present situation equilibrium between need for safe process appeal old, low process, there has recently been increasing interest deeply investigating utility fine chemicals such as heterocycles. assumption that expensive compounds, usually done amounts, should better tolerate use precious metals catalysts.