Verfahren zur Herstellung von aromatischen Thiocarbonsaeureamiden

摘要

Prepn. of thioamides from aromatic cpds. contng. a dihalomethyl group. The aromatic thioamides formed have Ar is aromatic in which the -CS group is directly attached to an aromatic ring. The method gives a cheap and convenient procedure for the prepn. of thioamides, which are used as intermediates for herbicides. ArCHX2+S+3NH3 (I)+2NH4X X = Cl, Br or iodine. The reaction is pref. carried out in the presence of a metal oxide such as calcium oxide or sodium hydroxide to take up HX and release ammonia for further reaction. An amine can be used in pace of ammonia.