J. Senet
Nov 1, 2000
Citations
0
Influential Citations
5
Citations
Quality indicators
Journal
Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule C-chimie
Abstract
Abstract Despite intensive research done to replace it with less noxious substitutes, phosgene is developing rapidly as an outstanding multipurpose tool in industrial organic chemistry. If phosgene is an extremely hazardous toxic gas, its main uses, strictly restricted to few specialized plants, give only benign environmental pollution, since the released by-products are hydrochloric acid and carbon dioxide. However, waste minimization requires highly selective and complete reactions and therefore efficient catalysts. The rational design of highly effective homogeneous, as well as heterogeneous phosgenation catalysts, especially hexaalkyl guanidinium chlorides, alternatively grafted on silica beads, has opened the route to environmentally improved processes. Moreover, the availability of such catalysts, combined with a better understanding of catalytic mechanisms resulted in the discovery of new selective cleaner processes to produce valuable pharmaceutical intermediates such as α-chlorinated carbonates or environmentally friendly reagents such as 1,1-dichloromethyl methyl ether. The new catalytic systems disclosed here, joined to major improvements of phosgenation techniques, opens the way to the design of non-salt and non-chlorinated waste generating routes to phosgene derivatives by recycling the released HCl.