Abstract:
In producing nabumetone or precursor thereof, use is made of 2-bromo-6-methoxynaphthalene formed by (a) methylating 6-bromo-2-naphthol with methyl bromide or methyl chloride, in a halogen-free liquid solvent comprising at least about 40% by weight of one or more compounds of the formula RZ where R is a hydrogen atom or an alkyl group, and Z is a hydroxyl group or a cyanide group with the proviso that if Z is a cyanide group, R is an alkyl group, and in the presence of at least one strong base; and (b) recovering and purifying 2-bromo-6-methoxynaphthalene so formed. The 6-bromo-2-naphthol in turn is preferably formed by reacting 1,6-dibromo-2-naphthol with hydrogen in a halogen-containing liquid solvent comprising at least about 50% by weight of (A) at least one liquid organic halide solvent in which the halogen content has an atomic number of 35 or less or (B) a mixture of water and at least one such liquid organic halide solvent, and in the presence of catalytic amounts of (i) a tungsten carbide-based catalyst, and (ii) at least one phase transfer catalyst, most preferably while purging HBr from the reaction mixture as it is formed. In this way, the quantities of by-products formed in the overall operation are reduced, the need for use of excess iron and/or dimethyl sulfate as reaction components is avoided, and the overall efficiency of plant operation is improved especially when conducted on a large scale.
Abstract:
A bromination process for organic compounds employs stabilized bromine chloride solutions as the brominating agent. Activated aromatic compounds such as anisole can be selectively monobrominated in the para-position in high purity and yield.
Abstract:
Described are multi-ring antioxidant products comprising at least one sulfur-bridged aromatic hydrocarbon compound substituted on at least one of its aromatic rings by at least one sterically hindered 3,5-dihydrocarbyl-4-hydroxybenzyl moiety. Such products have the formula: R—Sn—R[—S—R]m wherein each R is, independently, an aromatic hydrocarbon group having 6-12 carbon atoms, wherein m is 0-20, wherein n is 1-6 when m is 0, and when n is 1, m is 1-20; and wherein at least one of R, R1, and R2 is substituted by at least one such sterically hindered moiety. The preparation of such products and their use as antioxidants in compositions normally susceptible to oxidative degradation in oxygen or air, e.g., liquid fuel and lubricants, are also described.
Abstract:
This invention relates to novel macromolecular compositions having oxidation inhibition characteristics that are exhibited when added to organic material normally susceptible to oxidative degradation in the presence of air or oxygen, such a petroleum products, synthetic polymers, and elastomeric substances.
Abstract:
This invention provides aromatic diimines which have imino hydrocarbylidene groups with at least two carbon atoms, and aromatic secondary diamines which have amino hydrocarbyl groups with at least two carbon atoms. Both the aromatic diimines and the aromatic secondary diamines either are in the form of one phenyl ring, or are in the form of two phenyl rings connected by an alkylene bridge; each position ortho to an imino group or an amino group bears a hydrocarbyl group. When in the form of one phenyl ring, there are two imino groups on the ring or two amino groups on the ring; the imino groups or amino groups are meta or para relative to each other. When in the form of two phenyl rings connected by an alkylene bridge, there is either one imino group or one amino group on each phenyl ring. Also provided are processes for forming diimines and secondary diamines.
Abstract:
A mixture of water and a glycol, such as ethylene glycol, is employed as the solvent for the reaction between 1,6-dibromo-2-naphthol and an alkali metal sulfite in the preparation of 6-bromo-2-naphthol and its derivatives to effect a substantial reduction in reaction time. The glycol/water mol ratio is ordinarily in the range of 0.1-0.5/1, preferably 0.3/0.5/1.
Abstract:
Bromine is generated in situ in a mixture formed by mixing together 2-methoxynaphthalene, hydrogen bromide, at least one peroxidic compound and a chemically indifferent organic liquid solvent or diluent under conditions effective to produce 1,6-dibromo-2-methoxynaphthalene. Optionally, but preferably, water is also included in the mixture. Regioselective hydrodebromination of 1,6-dibromo-2-methoxynaphthalene with hydrogen and tungsten carbide enables production of 2-bromo-6-methoxynaphthalene.
Abstract:
In producing nabumetone or precursor thereof, use is made of 2-bromo-6-methoxynaphthalene formed by (a) methylating 6-bromo-2-naphthol with methyl bromide or methyl chloride, in a halogen-free liquid solvent comprising at least about 40% by weight of one or more compounds of the formula RZ where R is a hydrogen atom or an alkyl group, and Z is a hydroxyl group or a cyanide group with the proviso that if Z is a cyanide group, R is an alkyl group, and in the presence of at least one strong base; and (b) recovering and purifying 2-bromo-6-methoxynaphthalene so formed. The 6-bromo-2-naphthol in turn is preferably formed by reacting 1,6-dibromo-2-naphthol with hydrogen in a halogen-containing liquid solvent comprising at least about 50% by weight of (A) at least one liquid organic halide solvent in which the halogen content has an atomic number of 35 or less or (B) a mixture of water and at least one such liquid organic halide solvent, and in the presence of catalytic amounts of (i) a tungsten carbide-based catalyst, and (ii) at least one phase transfer catalyst, most preferably while purging HBr from the reaction mixture as it is formed. In this way, the quantities of by-products formed in the overall operation are reduced, the need for use of excess iron and/or dimethyl sulfate as reaction components is avoided, and the overall efficiency of plant operation is improved especially when conducted on a large scale.
Abstract:
Lubricants having a viscosity suitable for a refrigeration lubricant as well as good miscibility with common refrigerants (including R-134a) comprise at least one oil corresponding to the formula Z--C(E)(E').sub.p --Q.sub.s in which Z is alkyl, cycloalkyl, or --(CTT'--CT"G).sub.w --CTT'--CHT"G; Q is --(CTT'--CT"G).sub.t --CTT'--CHT"G; T, T', and T" are independently selected from hydrogen G', and organic groups containing up to 20 carbons; E, E', G, and G' are independently selected from --COOR, --C(O)R', and --CN electron withdrawing groups wherein R and R' represent hydrocarbyls containing 1-30 carbons, with the proviso that at least about 50% of the electron withdrawing groups are --COOR; p is zero or one; s is respectively two or one; and each of t and w represents zero or a positive integer.
Abstract:
Hydrogenated oligomers of C.sub.4 -C.sub.20 .alpha.-olefins are used in minor amounts to improve the lubricity of ester oils corresponding to the formula ROOC--CH.sub.2 CH.sub.2 --(ROOC--CHCH.sub.2).sub.m --C(COOR).sub.2 --(CH.sub.2 CHCOOR).sub.n --CH.sub.2 CH.sub.2 COOR in which the R's represent alkyl groups of 1-30 carbons, each of m and n is zero or a positive integer, and the sum of m and n in the molecules is an average of 0-30. The improved ester oils are particularly valuable for use as lubricants in refrigeration compositions containing fluorohydrocarbon refrigerants.