The present invention relates to a process for the preparation of compounds of the formula (1) in which R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are identical or different and are hydrogen, a halogen, an alkyl or alkoxy group having 1 to 6 carbon atoms or OR, NHR, NR.sub.2, SR or COOR, in which R is an alkyl radical having 1 to 4 carbon atoms, Ar is an aryl radical having 6 to 12 carbon atoms and the radical R shown in formula (1) has the above meaning, by reacting a compound of the formul...

A process for recovering 2,2-dimethylpropanoic acid in highly pure form from a mixture of 2,2-dimethylpropanoic acid and impurities which may be obtained in the production of a beta lactam antibiotic, by degrading impurities and separating off the volatile fragments.

Disclosed is a process for the production and purification of dialkyl naphthalenedicarboxylate compounds wherein a crude naphthalenediacarboxylic acid is esterified with an alkanol such as methanol to produce a crude esterification product comprising dialkyl naphthalenedicarboxylate, starting materials and other compounds and the crude esterification product is purified by flash distillation to remove impurities which can cause fouling of conventional distillation equipment. A particularly usefu...

Enol ethers of the formula I ##STR1## where R.sup.1 is an aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radical which may carry further substituents which do not react with acetylenes or allenes, and the radicals R, independently of one another, are hydrogen or aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radicals, which may be bonded to one another to form a ring, and m is 0 or 1, are prepared by reacting an acetal or ketal of the formula II ##STR2## with ...

Perfluoropropylvinylether (FPVE) purification process with C.sub.1 -C.sub.10 alcohols or mixtures thereof.

A hexafluoropropylene oxide oligomer of the formula: RfO[CF(CF.sub.3)CF.sub.2 O].sub.n CF(CF.sub.3)COF in which Rf is a group represented by the formula: F(CF.sub.2).sub.m -- in which m is an integer of 1 to 8, or the formula: (CF.sub.3).sub.2 CF(CF.sub.2)q-- in which q is an integer of 0 to 6, and n is a number of 3 to 20 is heated and thermally decomposed in a solvent at a temperature of at least 100.degree. C. in the presence of a compound which generates a fluoride (F.sup.-) ion to obtain ma...

A tertiary olefin such as isobutylene is reacted with a lower carboxylic acid to produce the ester in the presence of a large pore zeolite catalyst such as Zeolite Y, Zeolite beta or Zeolite X.

A process for obtaining (per) fluoropolyethers substituted at one or at both end groups with a halogen atom selected from bromine or iodine, having the formula: wherein A=B=halogen; or A=halogen and B=COOH or F, and the halogen is I or Br; p and q are integers such as to give a number average molecular weight (MW) in the range 350-5000 and the ratio p/q=0.5-2.0. The process includes treating di- or poly-acylperoxides having an average equivalent weight in the range 350-5000, of formula: with a h...

Lysine derivatives, salts of the derivatives, their optical isomers of D or L configuration, or their mixtures, the derivatives containing an N.sup.e -alkoxy or N.sup.e -alkenoxycarbonyl group and having the formula: ##STR1## in which: R represents a linear or branched C.sub.13 -C.sub.24 alkyl radical or alkenyl radicals, are used in cosmetic, pharmaceutical, hygiene or food compositions, particularly compact compositions.

The invention relates to polyether alcohols, to a process for preparing polyether alcohols by reacting alkylene oxides in the presence of a double metal cyanide (DMC) catalyst with at least one saturated OH component which may, if appropriate, have previously been reacted with an alkylene oxide, wherein an antioxidant is added before or during the reaction, and also to the further processing of the polyether alcohols to form polyurethanes.