Abstract: Halophthalic anhydrides are prepared by reaction of chlorine with a saturated or partially saturated halophthalic anhydride at a temperature of 200.degree. to 500.degree. Celsius.

Abstract: Novel polyimides and co-polyimides are prepared by the condensation polymerization of an aryl diamine with dioxydiphthalic anhydride or a mixture thereof with oxydiphthalic anhydride. The polyimides and co-polyimides prepared exhibit a low moisture absorption and improved dielectric properties and can be tailored to provide a composition having desirable mechanical properties, specifically, rigidity.

Abstract: Dioxydiphthalic anhydride is prepared by the reaction of dihalophthalic anhydride with an alkali metal compound, such as potassium carbonate. The compound is particularly useful as a monomer in the preparation of polyimides.

Abstract: A process for the preparation of halogen substituted phthalic anhydrides of the formula: ##STR1## wherein x is a halogen, by the reaction of a halogen substituted tetrahydrophthalic phthalic anhydride of the formula ##STR2## or a geminal dihalogen substituted hexahydrophthalic anhydride of the formula ##STR3## in a vapor or liquid phase while mixed with an air flow and an activated carbon catalyst at an elevated temperature.

Abstract: Halogen substituted aromatic compounds of the formula ##STR1## wherein Y is selected from the group CO.sub.2 H, COF, COCl, COBr, CF.sub.3, CN, NCO, or F, and X and X' are independently hydrogen or a halogen selected from the group F-, Cl- and Br-, at least one of X and X' being halogen; may be prepared by the liquid phase reaction of a brominating agent, at temperatures below about 190.degree. Celsius, with a correspondingly substituted cyclohexene or cyclohexadiene.

Abstract: 2-Chlorobenzylamine is prepared from 2-chlorobenzylchloride in a two-step process. In the first step, 2-chlorobenzylchloride is reacted with alkali metal phthalimide, preferably formed in situ from potassium carbonate and phthalimide, to form the novel intermediate 2-chlorobenzylphthalimide. In the second step, the phthalimide ring of the 2-chlorobenzylphthalimide is cleaved to form 2-chlorobenzylamine. The first step is preferably carried out in an unreactive solvent at 60.degree. C. to reflux temperature, for example, for 1 to 10 hours. The solvent is very preferably dimethylformamide which is advantageously recovered and used again as solvent in the conversion of 2-chlorobenzylchloride to 2-chlorobenzylphthalimide. The second step consists essentially, for example, of hydrazinolysis or hydrolysis.

Abstract: Phenoxy phthalic anhydrides are prepared by the reaction of a fluorophthalic anhydride with a phenol compound in the presence of potassium fluoride and a polar, aprotic solvent.

Abstract: A process for the preparation of 3-chloro-4,5-difluorobenzonitrile comprising the steps of(a) reacting an alkali metal fluoride with 4-chloro-3,5-dinitrobenzonitrile to form a 4-fluoro-3,5-dinitrobenzonitrile product;(b) chlorodenitrating the 4-fluoro product of step (a) to form the corresponding 3,5-dichloro-4-fluorobenzonitrile compound; and(c) reacting the 3,5-dichloro-4-fluorobenzonitrile compound prepared in step (b) with an alkali metal fluoride to form 3-chloro-4,5-difluorobenzonitrile.

Abstract: Oxydiphthalic anhydride is prepared by reacting an hydroxyphthalic anhydride with a bromophthalic or fluorophthalic anhydride and potassium fluoride in the presence of a solvent and a copper catalyst.

Abstract: Oxydiphthalic anhydrides are prepared by reacting a halophthalic anhydride with water and an alkali metal compound such as KF, CsF, or K.sub.2 CO.sub.3 in the presence of a copper catalyst.

Abstract: Novel halo-oxydiphthalic anhydrides are of the formula ##STR1## where X is F, Cl, Br, or I; X' is H, F, Cl, Br, or I.

Abstract: The instant invention relates to optically pure, L-(S)forms of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid compounds and their method of preparation from optionally pure L-phenylalanine precursor compounds and their preparation utilizing novel in situ cationic catalyst systems.

Abstract: Off-color liquid ortho-chloro-para-xylene compositions are decolorized by contacting the compositions with particles of diatomaceous silica, magnesium oxide or soda ash.

Abstract: 2,4,5-trifluorobenzoic acid is prepared by converting 4,5-di-fluoroanthranilic acid to the corresponding amine salt, converting the amine salt to the corresponding diazonium tetrafluoroborate and decomposing the tetrafluoroborate in a Schiemann reaction. In a preferred preparation, the 10 percent HCl is added to solid 4,5-difluoroanthranilic acid in sufficient amount to dissolve the solid at 70.degree. C., the amine salt is isolated, aqueous NaNO.sub.2 is added to the isolated amine salt at 0.degree. C., followed by addition of 40 to 50 percent aqueous HBF.sub.4 at 0.degree. C., followed by separation of the tetrafluoroborate by cooling and filtering and then drying, and the dried separated tetrafluoroborate is thermally degraded to 2,4,5-trifluorobenzoic acid by heating at 125.degree. to 140.degree. C.

Abstract: The present invention provides a process for the preparation of 2-(2-thienyl)-ethylamine and derivatives thereof having the general formula: ##STR1## wherein R.sub.1 and R.sub.2 are hydrogen or taken together form a phenyl ring.

Abstract: A mixture of telomers prepared by reacting chlorotrifluoroethylene with 1,1,2-trichlorotrifluoroethane (CCl.sub.2 FCF.sub.2 Cl) is purified by reacting the telomer mixture with potassium hydroxide in the presence of a quarternery ammonium compound and, optionally, a glycol, separating and removing impurities from the telomer mixture, subsequently reacting the telomer with potassium permanganate in the presence of the quarternery ammonium compound in a solvent, and recovering a purified telomer mixture.If additional purity is required, the purified telomer mixture can be heated to a temperature of from about 150.degree. C. to about 250.degree. C. for at least 12 hours, and impurities formed during the thermal treatment are removed.The purified telomers of this invention find uses in applications requiring the use of non-flammable hydraulic fluids.

Abstract: A hot-dip galvanized coating for improved resistance welding of galvanized steel parts or sheets includes particles of a metal phosphide, and preferably ferrophosphorus particles, having a particle size of from about 0.1 to about 30 microns such particles being included in the galvanized coating while the zinc is still molten. The coating can also include up to about 40% by weight of the metal phosphide of an additional metal such as nickel, tin, aluminum or lead, which can be incorporated in the coating as discrete particles or deposited onto the surface of the metal phosphide particles.The advantages of the present invention include a significant reduction in welding current and an increase in electrode life, as well as simplified application of the coating by incorporating the metal phosphide particles directly into existing coating lines.

Abstract: Oxydiphthalic anhydrides of the formula ##STR1## are prepared by reacting a halophthalic anhydride with potassium carbonate in:(1) a solvent-free reaction medium wherein the molar ratio of halophthalic anhydride:potassium carbonate is greater than 2:1; or(2) a high boiling solvent which improves the mixing of the components, and aids in subsequent purification of the product. The molar ratio of halophthalic anhydride to potassium carbonate is about 1.5:1 or greater.The oxydiphthalic anhydride can be purified by filtering or centrifuging a hot solution of the oxydiphthalic anhydride in a high boiling solvent to remove impurities, followed by cooling the solution to precipitate the oxydiphthalic anhydride, which can be removed from the solution by filtration or centrifuging.

Abstract: Diether diphthalic anhydrides are prepared by reacting fluorophthalic anhydride with an aromatic dihydroxyl compound in the presence of potassium fluoride and a polar, aprotic solvent.

Abstract: Oxy-diphthalic anhydrides are prepared by reacting a halophthalic anhydride with an hydroxyphthalic anhydride in a polar aprotic solvent and in the presence of an alkali metal compound such as KF, CsF or K.sub.2 CO.sub.3.