Method for the phosgenation of compounds comprising hydroxyl, thiol, amino and/or formamide groups

A method of reacting a first compound with a second compound,

• wherein the first compound has a GHS hazard identification of GHS06 and is obtainable from the reaction of at least one first fluid precursor compound and one second fluid precursor compound and
• wherein the second compound is capable of a chemical reaction with the first compound, comprising:
• (I) providing a liquid phase containing the second compound in a reactor having an upper end and a lower end viewed in the direction of gravity;
• (II) providing a contact tube having an upper end and a lower end in the reactor,
• wherein the lower end of the contact tube is immersed into the liquid phase containing the second compound and a catalyst bed present in the contact tube is set up to catalyze the reaction between the first and second precursor compounds to give the first compound;
• (III) introducing the first and second precursor compounds through the contact tube, with the first compound formed in the contact tube exiting from the lower end of the contact tube and coming into contact with liquid phase containing the second compound,
• wherein the first compound is phosgene, the first precursor compound is carbon monoxide, the second precursor compound is chlorine, the catalyst present in the catalyst bed is an activated carbon catalyst and the second compound is a compound containing one or more of hydroxyl, thiol, amino and/or formamide groups.