Catalyst for aromatic e.g. phenyl mono:isocyanate prodn. - contg. palladium chloride, a Gp=VB metal oxide, a Gp=VIB metal oxide, and a pyridine or alkyl-substd. pyridine (AT 15.4.81)

摘要

New catalyst (I) for the synthesis of aromatic monoisocyanates contains (A) 1.64-16.6 wt.% palladium chloride, (B) 0.16-47.6 wt.% of a group Vb metal oxide, (C) 1.5-81.8 wt.% of a group VIb metal oxide, and (D) pyridine or an alkyl-substd. pyridine to 100 wt.% (I) is used, in the prodn. of aromatic monoisocyanates such as phenyl isocyanates, useful as intermediates for non-toxic agricultural chemicals, and mono- and dichloro-substd. monophenyl isocyanates useful as intermediates for pesticides and plant growth regulators. Using the new catalyst, which has a relatively low palladium cpd., conversion of nitro cpds. into isocyanates is 95-100% and yields of isocyanates are 66-97%. Throughput is 10-39 g end product per g. PdCl2 per hr.