Abstract: The present invention relates to the preparation of alkyl-ureas, starting from O,S-dimethyl dithiocarbonate, which provides the following steps: A) causing the O,S-dimethyl dithiocarbonate to react with a primary amine of general formula R1NH2 in order to obtain an O-methyl thiocarbamate; B) isomerising the O-methyl thiocarbamate in order to obtain an S-methyl thiocarbamate; C) causing the S-methyl thiocarbamate with a compound of general formula R′R″NH, wherein R′ and R″ may be equal or different one in respect of the other and of R1 and may be H, R2 or R3, in order to obtain one of the alkyl-ureas of formula (4), (5) or (6).

Abstract: A new process is described for the preparation of trithiocarbonic acid esters of formula: ##STR1## in which R and R.sub.1, which can be the same or different, are aliphatic, alicyclic, aromatic or heterocyclic radicals. The new process is characterized in that an organic hydrosulphide and a base, or an inorganic sulphide, are reacted with carbon disulphide and an organic halide in stoichiometric proportions in the absence of organic solvents, in the presence of an aqueous phase and a phase transfer catalyst.

Abstract: Process for preparing alkyl-sulphonyl chlorides and arylalkyl-sulphonyl chlorides of formula RSO.sub.2 Cl (R being alkyl or arylalkyl), starting from S,S-dialkyl or diarylalkyl dithiocarbonates RS--CO--SR, consisting in reacting the starting compound with gaseous chlorine in the presence of water, at 0.degree.-+10.degree. C.

Abstract: A process for preparing organic thioethers of formula R--S--R.sub.1 in which R is an aliphatic, aryl, arylaliphatic or heterocyclic radical and R.sub.1 is an aliphatic or arylaliphatic radical, from organic dithiocarbonates and organic halides or sulphonates, in the presence of an aqueous alkaline base and a phase transfer catalyst, at a temperature of between 50.degree. and 100.degree. C. for a time of 10-60 minutes.