Abstract: The present invention relates to a carbonic acid ester compound of the following formula (1): in which X, Y, and Ar are defined in the specification, which can be easily combined with the amino group of an amino acid or removed therefrom under mild conditions, whereby the amino group can be effectively protected during peptide syntheses, process for preparing the same, and use of the same. Since the amino acid derivatives thus protected have high thermal and chemical stabilities and good solubility for organic solvents, peptides can be synthesized at a low cost with a high yield.

Abstract: The invention concerns a method for phosgenation of monohydroxy alcohol's and/or polyols characterised in that it consists of treating alcohol and or polyol, whether in the presence of solvent or not, with a molar excess of phosgene, preferably 2 to 30 times more phosgene than the hydroxyl groups, at temperatures ranging between 0 and 200° C. and at pressure levels ranging between 2 and 60 bar, preferably in the absence of any catalyst. The method is further characterised in that pressure is further used to facilitate the separation of hydrochloric acid from phosgene, in a column external to the reactor.

Abstract: Novel catalysts for the synthesis of a alpha-chlorinated chloroformate from an aldehyde and phosgene are described. The catalysts include alkyl substituted guanidines, hexasubstituted guanidinium chlorides, substituted biguanidinium chloride, phenyldialkyliminiumtetraalkylguanidinium chloride, dialkylimidazolinium tetraalkylguanidinium chloride, phenyltetraalkylamidinium chloride and N,N-dialkyl-N'-alkylpyrrolidinium chloride.

Abstract: The compounds of the present invention are adaptable as blocking or protecting groups for an amine composition useful in peptide synthesis. The present invention is directed to a method of protecting an amino group of an organic molecule during a reaction which modifies a portion of the molecule other than the protected amino group.

Abstract: Ethyl chloroformate is chlorinated in the rectifying zone of a distillation reactor to produce 1-chloroethyl chloroformate and 2-chloroethyl chloroformate.

Abstract: This invention relates to compounds of the formula: ##STR1## wherein R is an electron withdrawing group;R.sub.1 is H or COZ;X.sub.1 and X.sub.2 are independently H, lower alkyl, aryl, aryl lower-alkyl or polystyrene or R and X.sub.1 taken together with the carbon atoms to which they are attached form a ring containing from 4 to 15 ring carbon atoms and may contain up to 2 heteroatoms, wherein the heteroatoms are O, S, or N; andZ is an amino acid residue, a peptide residue or a leaving group. The compounds of the present invention are adaptable as blocking or protecting groups for an amine composition useful in peptide synthesis. The present invention is also directed to a method of protecting an amino group of an organic molecule during a reaction which modifies a portion of the molecule other than the protected amino group.

Abstract: The subject of the invention is functional chlorofluoro compounds of general formula: ##STR1## in which R.sub.F denotes a perfluoroalkyl radical, n is equal to 0 or 1, X denotes a chlorine or fluorine atom or a trichloromethyl or trifluoromethyl radical, and Y denotes a chlorine atom, an optionally salified or esterified hydroxyl group or an optionally substituted amino group, the arrangement R.sub.F --CCl.sub.2 --(CCl.sub.2 --O).sub.n containing at least 3 carbon atoms.By photochlorination of the esters R.sub.F --CH.sub.2 CH.sub.2 --O--CO--X, the compounds I (n=1) are obtained, which are then rearranged to acid chlorides I (n=0, Y.dbd.Cl) from which the corresponding acids, salts, esters and amides are optionally formed (formula I with n=0 and Y=optionally salified or esterified hydroxyl or optionally substituted amino).

Abstract: Normally liquid peroxidic poly(perfluorooxyalkylene) compositions comprising a mixture of peroxidic poly(perfluorooxyalkylene) compounds, derivatives of the poly(perfluorooxyalkylene) compositions comprising a mixture of non-peroxidic polyfluoropolyether compounds, and derivatives of the polyfluoropolyether compositions comprising functional and non-functional derivatives of the polyfluoropolyether compositions are provided. Each peroxidic poly(perfluorooxyalkylene) compound comprises a backbone of randomly distributed perfluorooxyalkylene units, represented by the formulas ##STR1## which when bonded to an --O-- of any of the perfluorooxyalkylene units, forms a peroxy group, --O--O--, which imparts the peroxidic characteristics to the material, and backbone-pendant perfluoroalkoxy groups or perfluoroalkoxy groups substituted with one or more ether oxygen atoms, the terminal ether oxygen atoms of which are bonded to carbon atoms of the ##STR2## backbone units.

Abstract: A method is provided for determining the stoichiometric end point of phosgenation reactions which produce polycarbonates and chloroformates, respectively, by monitoring the rate of heat generated by the reaction mixture per unit of phosgene utilized.

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: 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: Normally liquid peroxidic poly(perfluorooxyalkylene) compositions comprising a mixture of peroxidic poly(perfluorooxyalkylene) compounds, derivatives of the poly(perfluorooxyalkylene) compositions comprising a mixture of non-peroxidic polyfluoropolyether compounds, and derivatives of the polyfluoropolyether compositions comprising functional and non-functional derivatives of the polyfluoropolyether compositions are provided. Each peroxidic poly(perfluorooxyalkylene) compound comprises a backbone of randomly distributed perfluorooxyalkylene units, represented by the formulas --CF.sub.2 O--, ##STR1## and --O--, which when bonded to and --O-- of any of the perfluorooxyalkylene units, forms a peroxy group, --O--O--, which imparts the peroxidic characteristics to the material, and backbone-pendant perfluoroalkoxy groups or perfluoroalkoxy groups substituted with one or more ether oxygen atoms, the terminal ether oxygen atoms of which are bonded to carbon atoms of the ##STR2## backbone units.

Abstract: A method is provided for determining the stoichiometric end point of phosgenation reactions which produce polycarbonates and chloroformates, respectively, by monitoring the rate of heat generated by the reaction mixture per unit of phosgene utilized.

Abstract: A method is provided for making reaction products of phosgene and dihydric phenol, such as bischloroformates and polycarbonates utilizing a reactor with an overhead condenser. Reduced phosgene blow-by is achieved by using an absorber for phosgene which is connected in series to the overhead condenser.

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 novel compound .alpha.-bromodiethylcarbonate, novel methods for the preparation thereof, its use in the preparation of 1-ethoxycarbonyloxyethyl esters of penicillins and cephalosporins, and improvements in the method for preparing such esters.

Abstract: Process for the synthesis of .alpha.-chlorinated chloroformates, and new .alpha.-chlorinated chloroformates.The invention relates to a new process for the manufacture of .alpha.-chlorinated chloroformates and, to new .alpha.-chlorinated chloroformates as new industrial products.The process according to the invention consists of a synthesis, by catalytic phosgenation, of .alpha.-chlorinated chloroformates of the formula: ##STR1## in which: R represents a substituted or unsubstituted hydrocarbon radical and m represents an integer superior or equal to one, this synthesis consisting in reacting phosgene with the aldehyde R--CHO).sub.m, in the presence of a catalyst which is an organic or inorganic substance which is capable in a medium containing an aldehyde of the formula R--CHO).sub.

Abstract: Process for the synthesis of .alpha.-chlorinated chloroformates, and new .alpha.-chlorinated chloroformates.The invention relates to a new process for the manufacture of .alpha.-chlorinated chloroformates and, to new .alpha.-chlorinated chloroformates as new industrial products.The process according to the invention consists of a synthesis, by catalytic phosgenation, of .alpha.-chlorinated chloroformates of the formula: ##STR1## in which: R represents a substituted or unsubstituted hydrocarbon radical and m represents an integer superior or equal to one, this synthesis consisting in reacting phosgene with the aldehyde R--CHO).sub.m, in the presence of a catalyst which is an organic or inorganic substance which is capable in a medium containing an aldehyde of the formula R--CHO).sub.