Abstract: A process for the preparation of fluoroformates of the formula wherein R1 is a saturated or unsaturated, substituted or unsubstituted and primary or secondary aliphatic, a saturated or unsaturated, substituted or unsubstituted secondary cycloaliphatic or a substituted or unsubstituted aromatic or heteroaromatic, and n is equal to 1, 2 or 3, comprising reacting a corresponding chloroformate of formula I with an alkali metal fluoride in ethylene carbonate at a temperature wherein the ethylene carbonate is liquid whereby it is possible to very rapidly obtain the fluoroformates with excellent yields and high purity.

Abstract: A process for the preparation of fluoroformates of the formula 1

Abstract: The subject of the invention is a new process for the preparation of alkyl thiochloroformates.The process according to the invention consists in reacting phosgene with a mercaptan in the presence of a catalyst which is a hexaalkylguanidinium chloride or the corresponding hydrochloride of general formula: ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 represent alkyl radicals containing 1 to 4 carbon atoms and in which n may take either the value 0 or the value 1.The preferred catalysts are hexamethylguanidinium chloride and its hydrochloride.The process according to the invention enables very pure alkyl thiochloroformates to be obtained with milder operating conditions and simplified purification operations.

Abstract: The invention relates to a process for the preparation of 1-bromoethyl hydrocarbonyl carbonates, characterized in that anhydrous hydrobromic acid is reacted with a vinyl hydrocarbonyl carbonate of formula ##STR1## in which R denotes a saturated, substituted or unsubstituted C.sub.1 -C.sub.12 aliphatic radical or C.sub.5 -C.sub.24 alicyclic radical, or a substituted or unsubstituted aromatic radical, at a temperature between 10.degree. and 100.degree. C.The invention also relates to the new 1-bromoethyl hydrocarbonyl carbonates of formula: ##STR2## These carbonates are particularly sought after for introducing a carbonate group into a molecule.

Abstract: Vinyl chloroformates are described of formula ##STR1## in which: R.sub.1 .dbd.R.sub.2 .dbd.Cl, Br or a saturated 1-4 carbon atom alkyl or together they form a cycloaliphatic ring of 4-8 carbon atoms;R.sub.3 .dbd.H when R.sup.1 or R.sup.2 .dbd.alkyl; saturated alkyl of 1-4 carbon atoms or aryl; ##STR2## in which R.sub.4 .dbd.R.sub.5 .dbd.alkyl of 1-4 carbon atoms or R.sub.3 forms with R.sub.2 a C.sub.5 -C.sub.8 ring which may have attached oxygen atoms. The process of preparation consists of reacting phosgene with the corresponding compounds containing alpha halogen and a carbonyl group. The products are very useful to obtain vinyl carbonates and carbamates.

Abstract: The invention relates to a new process for the preparation of carboxylic acid chlorides by phosgenation of the corresponding carboxylic acid in the presence of a catalyst.This process is characterized in that the said catalyst is chosen from the compounds represented by the formulae ##STR1## in which R.sub.1 to R.sub.6, which are identical of different, denote: aliphatic, alicyclic, araliphatic or aromatic radicals,or form, in pairs, with the nitrogen atom to which they are attached or with the N-C-N group, a 5- or 6-membered heterocyclic ring.The process applies to most carboxylic acids.The acid chlorides obtained are known and used to produce radical polymerization initiators or pesticides.

Abstract: Novel 2,2-dihalovinyl haloformates are described of general formula: ##STR1## in which: X is a chlorine or bromine atom;X.sub.1 and X.sub.2 are the same or different and are chlorine or bromine.The compounds are prepared by reaction of a 1,2,2,2-tetrahaloethyl haloformate of formula: ##STR2## in which: X.sub.1, X.sub.2 and X are as described hereinabove;X.sub.3 is chlorine or bromine and is always bromine when X.sub.1 and/or X.sub.2 is bromine andX.sub.4 is chlorine or bromine, with a metal such as zinc or magnesium in a solvent.The novel compounds are very useful for the preparation of 2,2-dihalovinyl carbonates and carbamates which may be used as insecticides or as comonomers.

Abstract: The invention relates to a process for the preparation of 1-bromoethyl hydrocarbonyl carbonates, characterized in that anhydrous hydrobromic acid is reacted with a vinyl hydrocarbonyl carbonate of formula ##STR1## in which R denotes a saturated, substituted or unsubstituted C.sub.1 -C.sub.12 aliphatic radical or C.sub.5 -C.sub.24 alicyclic radical, or a substituted or unsubstituted aromatic radical, at a temperature between 10.degree. and 100.degree. C.The invention also relates to the new 1-bromoethyl hydrocarbonyl carbonates of formula: ##STR2## These carbonates are particularly sought after for introducing a carbonate group into a molecule.

Abstract: Process for the preparation of .alpha.-chlorinated chloroformates with the formula ##STR1## where R is H, an aliphatic or aromatic hydrocarbon radical or heterocyclic radical, substituted or non-substituted and n an integer.The process consists of reacting ClCOOCCl.sub.3 or Cl.sub.3 COCOOCCl.sub.3 with an aldehyde with formula R--(CHO).sub.n in the presence of a compound, which in the medium releases a pair of ions, the anion of which being a halide which can attack the aldehyde function, because of the weak attractive power of the cation of this compound.

Abstract: The invention relates to a process for the preparation of halogeno-mercuri-aldehydes and -ketones.According to the invention, an alkenyl ester is reacted with a mercuric halide in the presence of water and, preferably, of an acid acceptor. The reaction, which is preferably carried out at between 15.degree. and 35.degree. C., makes it possible to obtain very pure products with excellent yields, especially when mercuric oxide is used as the acid acceptor.

Abstract: The invention relates to a process for the industrial scale synthesis of vinyl and isopropenyl chloroformates and thiochloroformates.According to the invention, phosgene or thiophosgene is reacted, at between 20.degree. and 70.degree. C., with a mercury salt XHg(CH.sub.2 CRO), in which X=Cl or --CH.sub.2 CRO, where R=H or CH.sub.3, in the presence of a solvent or a mixture of solvents having a dielectric constant greater than 10. The process can also be carried out using a mixture of the above solvents with a solvent which is not effective by itself (solvent of low polarity) but which is inexpensive. The yields achieved can exceed 90%.