Famous Patents
In 1608, Dutch eyeglass maker Hans Lipperhey filed the first patent for a working telescope. The patent was denied.
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 8134016 | Method for purifying dianhydrides A method for purifying dianhydrides is provided. In one aspect, purified oxybisphthalic anhydrides, intermediates useful in the preparation of polyetherimides are provided. In one embodiment, a first solution containing a dianhydride compound, a solvent, and a phase... | 03/13/2012 |
| 7009063 | Process for the production of oxandrolone The present invention relates to a process for the synthesis of oxandrolone from mestanolone. The process comprises the steps of: (a) oxidizing mestanolone to form 17β-hydroxy-17α-methyl-5α-androst-1-en-3-one; (b) hydroxylating the 17β-hydroxy-17α-methyl-5α-an... | 03/07/2006 |
| 6204394 | Method for preparing oxy-diphthalic anhydrides Disclosed is a method for preparing oxy-diphthalic anhydrides, which comprises reacting a halo-phthalic anhydride represented by the formula (1): ##STR1## where Hal represents F, Cl, Br or I, with a carbonate salt selected from the group consisting o... | 03/20/2001 |
| 6136949 | Resins containing phenylethynl-terminated compounds A compound of the formula: ##STR1## wherein Ar1 is the backbone of any aromatic diamine moiety other than 3,4'-oxydianiline and W independently in each occurrence is a bond or a radical selected from the group consisting of: ##STR2##... | 10/24/2000 |
| 6060575 | 1,4-bis(3,4-dicarboxyphenoxy)-2-tert-butylbenzene dianhydride and method of using the same The present invention provides a series of easily processable poly(ether-imide)s that are organic-soluble and can afford colorless films, their organic solutions and their manufacturing process. The poly(ether-imide) is prepared from a dianhydride and a d... | 05/09/2000 |
| 5681967 | Phenylethynyl phthalic anhydride Controlled molecular weight phenylethynyl terminated imide oligomers (PETIs) have been prepared by the cyclodehydration of precursor phenylethynyl terminated amic acid oligomers. Amino terminated amic acid oligomers are prepared from the reaction of dianh... | 10/28/1997 |
| 5675020 | Ortho-bis(etherdianhydrides) Disclosed herein are novel poly(imide-ethers) containing ortho substitution in the main chain of the polymer. These polymers are made from novel aromatic bis-carboxylic anhydrides which contain two ether groups attached to an aromatic ring in ortho positi... | 10/07/1997 |
| 5424278 | Hydroxycornexistin Hydroxycornexistin (1), the free dibasic acid thereof (2) ##STR1## agronomically acceptable bis-ester, monoester, monoamide, and monothioesters thereof, and agronomically acceptable salts thereof are selective herbicides for broad spectrum broadleaf ... | 06/13/1995 |
| 5206429 | Nitration reactions with acid anhydride promoters An improved all nitric acid nitration process for the nitration of phthalic acid, phthalic anhydrides and derivatives thereof wherein the improvement consists essentially of employing a rate enhancing amount of a nitration promoting inorganic acid anhydri... | 04/27/1993 |
| 5155234 | Nitration of phthalic acid and phthalic anhydride using nitric acid A process for the preparation of nitrophthalic acid by the nitration of phthalic acid and/or phthalic anhydride using only nitric acid, said nitric acid having a concentration of at least about 95% by weight, and then recovering the nitrophthalic acid for... | 10/13/1992 |
| 5153335 | Process for the preparation of oxydiphthalic anhydride and acyloxyphthalic anhydrides A method for the preparation of acyloxyphthalic anhydride or oxydiphthalic anhydride which comprises the reaction of a halophthalic anhydride with an alkali metal salt and at least a catalytically effective amount of an acid or acid derivative selected fr... | 10/06/1992 |
| 4996316 | Process for the preparation of tertiary N, N-dimethylamines A process for the preparation of tertiary N,N-dimethylamines by the reaction of primary amines, formaldehyde, and hydrogen under pressure and at elevated temperature in the presence of a nickel-containing hydrogenation catalyst in the liquid phase. The hy... | 02/26/1991 |
| 4960905 | Phenoxy phthalic anhydrides 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.... | 10/02/1990 |
| 4897104 | Anhydride herbicides A novel compound named "cornexistin" has the formula (I): ##STR1## and it and the corresponding ring-opened diacid and salts thereof have herbicidal and growth regulating effects. Cornexistin can be prepared by cultivation of a microorganism of the g... | 01/30/1990 |
| 4870173 | Lactam formation by a selective cyclization process This invention provides a process for preparing lactams, by selectively reacting a novel 1-hydrocarbyl-amino (or heteroatom-substituted hydrocarbylamino); 1,1-dicarboxylic acid, alkylesters; 1-hydrocarbyl (or heteroatom-substituted hydrocarbyl) carboxylic... | 09/26/1989 |
| 4835268 | Luminescent cyclic hydrazides for analytical assays Disclosed herein are derivatives of 5-(lower alkyl)-7-amino-2,3-dihydro-1,4-phthalazinedione having substituents on the amino group. The derivatives have luminescent properties which render them useful as analytical tools in clinical chemistry. Adaptation... | 05/30/1989 |
| 4827000 | Process for the preparation of phenoxy phthalic anhydrides 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.... | 05/02/1989 |
| 4785114 | Quinophthalone dyes Quinophthalone dyes of the formula ##STR1## where X is O or NC--C--R, where R is cyano, unsubstituted or N-substituted carbamyl, carboalkoxy, quinazolonyl, quinoxalinonyl, benzimidazolyl or benzothiazolyl and the rings A, B, the quinoline system and/... | 11/15/1988 |
| 4785120 | Process for preparing substituted phthalic anhydrides Yield and assay (purity) improvements in the reaction of bromine and the Diels-Alder addition product of maleic anhydride and a conjugated diene in the presence of a nitrogenous acid acceptor are realized in the instant process. The heating time after com... | 11/15/1988 |
| 4758661 | Chiral synthesis of (+)-trans-1a,2,3,4a,5,6-hexahydro-9-hydroxy-4-propyl-4H-naphth[1,2-b]-1, 4-oxazine (+)-trans-1a,2,3,4a,5,6-Hexahydro-9-hydroxy-4-propyl-4H-naphth[1,2-b]-1,4-o xazine is elaborated by a series of process steps that retain the enantiomeric purity of the starting material, D-aspartic acid. The product is a direct acting dopaminergic agent, ... | 07/19/1988 |
| 4748255 | Thermally adaptive polymers and prepolymers and methods of making them Reaction of an aromatic dianhydride with a polycyclic aromatic primary diamine at a controlled reaction rate yields a diamic acid dianhydride oligomer. The oligomer may be a precursor for an imide foam which forms at low temperature, has outstanding physi... | 05/31/1988 |
| 4684737 | Process for producing substituted phthalic acid compounds A process for producing a substituted phthalic acid which comprises heating a substituted tetrahydrophthalic acid compound having a substituent in at least one of the 3-, 4-, 5- and 6-positions in the presence of sulfur to dehydrogenate it, and heat-treat... | 08/04/1987 |
| 4650880 | Purification of substituted phthalic anhydrides A process for purifying crude substituted phthalic anhydrides, e.g. 4-methylphthalic anhydride, derived from the dehydrogenation in the presence of bromine of a Diels-Alder addition product of a conjugated diene, e.g. isoprene, and maleic anhydride. In th... | 03/17/1987 |
| 4596876 | Phthalaldehyde adducts Novel adducts of phthalaldehyde are disclosed, as well as imaging compositions and imaging elements incorporating them. A method is also disclosed for minimizing dimensional changes in the element during processing.... | 06/24/1986 |
| 4559405 | Process for preparing substituted phthalic anhydrides A process for preparing substituted phthalic anhydrides, e.g. 4-methylphthalic anhydride, in which the Diels-Alder addition product of a conjugated diene, e.g. isoprene, and maleic anhydride is reacted with bromine in the presence of an acid acceptor. Typ... | 12/17/1985 |
| 4537977 | Tetrasubstituted phthalic acid derivatives, and a process for their preparation Novel tetrasubstituted phthalic acid derivatives of the formula ##STR1## are described, in which Y1 and Y2 are oxygen and Y is ##STR2## or --O--, or one of Y1 and Y2 is oxygen and the other is .dbd.N--... | 08/27/1985 |
| 4533772 | Process for directly hydroxylating olefins using an osmium-halide catalyst and oxygen oxidant The process for hydroxylating olefins with oxygen in the presence of water, an osmium-halide (e.g., OsBr3) catalyst and transition metal containing co-catalyst (CuBr2) is disclosed.... | 08/06/1985 |
| 4526984 | Autoxidation of alkyl-substituted aromatic ethers A method is described for autoxidizing ortho-dialkyl substituted aromatic ethers directly to their corresponding carboxylic acid anhydrides. The method comprises autoxidizing the ethers in a first step in a solution of an aliphatic monocarboxylic acid hav... | 07/02/1985 |
| 4486613 | Process for hydroxylating olefins using an osmium carbonyl catalyst A process for hydroxylating olefins, such as ethylene or propylene, using an oxidant selected from organic hydroperoxides, H2 O2, and oxygen and a catalyst composition comprising at least one osmium carbonyl catalyst, such as Os... | 12/04/1984 |
| 4482763 | Process for hydroxylating olefins in the presence of an osmium containing catalyst and organic halogenated hydrocarbon co-catalyst A process for hydroxylating olefins with an organic hydroperoxide and water in the presence of an osmium containing catalyst (e.g. OsO4) and an organic halogenated hydrocarbon co-catalyst (e.g., n-butyl iodide) is disclosed.... | 11/13/1984 |
| 4480105 | 3,5-Disubstituted phthalic acids and phthalic anhydrides Novel compounds of the formula II ##STR1## are described, in which M1 and M2 individually are --OH or together are --O--, X is --NO2, --OR', --SR' or SO2 R' and the (R')s independently of one another are C | 10/30/1984 |
| 4413151 | Process for hydroxylating olefins using a supported osmium catalyst A process for hydroxylating olefins using a supported osmium catalyst such as Os3 (CO)12 adsorbed on a support, such as MgO, and optionally in conjunction with a co-catalyst such as NaI, is disclosed.... | 11/01/1983 |
| 4390739 | Hydroxylation of olefins A process directed to the hydroxylation of olefins by reacting said olefins with an oxygen containing gas and water in the presence of a catalyst composition comprising (i) a catalytically active metal oxide such as OsO4, (ii) as a co-catalyst ... | 06/28/1983 |
| 4363917 | 3,5-Disubstituted phthalic acid imides, phthalic acids and phthalic acid anhydrides Novel compounds of the formula I or II ##STR1## are described, in which M1 and M2 individually are --OH or together are --O--, R is hydrogen, C1-20 -alkyl, C2-5 -alkenyl, C3-5 -alkynyl, C5-1... | 12/14/1982 |
| 4314088 | Hydroxylation of olefins Method for preparing polyols such as diols and triols by the homogeneous catalytic hydroxylation of an olefinic compound by contacting the olefinic compound with an organic hydroperoxide in an inert polar solvent containing catalytic amounts of an osmium ... | 02/02/1982 |
| 4261898 | Silicon-modified phthalic acid derivatives The invention relates to Si-modified phthalic acid derivatives (acids, esters and anhydrides) of the formula I ##STR1## in which R1 and R2 independently of one another are --OH, alkoxy with 1-12 C atoms or phenoxy or R1 | 04/14/1981 |
| 4210749 | Substituted 1,2,4,5-tetrahydro-3H,3 benzazepines Compounds of the general formula: ##STR1## and pharmaceutical acceptable salts thereof wherein R is H, lower alkyl, lower alkenyl, lower aralkenyl, cycloalkyl-alkyl, propargyl, lower aralkyl, hydroxyalkyl and esters thereof, heterocyclic, hetero... | 07/01/1980 |
| 4186269 | Process for producing an aromatic urethane An aromatic urethane is obtained at high yield without involving corrosion of a stainless steel reactor by interacting an aromatic nitro compound, an organic compound having at least one hydroxyl group therein and carbon monoxide in the presence of a cata... | 01/29/1980 |
| 4140703 | Phthalic acid derivatives substituted by alkenylamino groups Novel phthalic acid derivatives, especially phthalic anhydrides, which are substituted by alkenylamino groups, and a process for their preparation are described. The novel phthalic acid derivatives are valuable intermediates for the preparation of corresp... | 02/20/1979 |
| 4138412 | Simultaneous production and purification of 4-nitro-omicron-phthalic anhydride A process for the simultaneous production and purification of 4-nitro-o-phthalic anhydride which comprises subjecting an impure mixture containing 4-nitro-o-phthalic acid to azeotropic dehydration with selected azeotroping agents.... | 02/06/1979 |
