Abstract:
Catalysts of protein-disulfide isomerization of formula: where R1 is hydrogen or —COR4, where R4 is an optionally substituted aliphatic group or an optionally substituted aryl group; R2 is hydrogen or —CO—R5, where R5 is alkyl having 1-8 carbon atoms, an alkenyl having 3-8 carbon atoms or a phenyl, benzyl, phenethyl or naphthyl group; and R3 is hydrogen or alkyl group having 1-3 carbon atoms. Protein folding buffers comprising one or more of the above compounds. Method of catalyzing, in vivo or in vitro, the isomerization of disulfide linkages in a protein or peptide employing above catalysts. Method of forming, in vivo or in vitro, disulfide linkages in a protein or peptide employing above catalysts.
Abstract:
A supported catalyst for aldehyde coupling reaction, comprising a carrier having supported thereon a catalyst comprising at least one azolium compound selected from the group consisting of a thiazolium salt, an imidazolium salt, a benzimidazolium salt and a triazolium salt, the azolium compound having, at a nitrogen atom thereof, a substituent selected from the group consisting of an aliphatic group having 6 or more carbon atoms and an aromatic group having 6 or more carbon atoms.
Abstract:
A functional group-selective hydrogenation catalyst is provided, which is capable of selectively hydrogenating an aliphatic carbon-carbon double bond, aliphatic carbon-carbon triple bond, aromatic formyl group or aromatic nitro group contained in an organic compound. The catalyst includes a carrier, and palladium and an organic sulfur compound supported jointly thereon.
Abstract:
The invention relates to a catalytic method for the production of aliphatic and aromatic carbonyl compounds with at least one aldehyde or ketone function, whereby said compounds can also comprise at least one aldehyde and ketone function. A starting material comprising at least one aliphatic- and/or aromatic-bonded functional group of formula (I), where R1=H, alkyl or aryl, X=H, or a group which may be substituted by the sulphinyl group of a sulphoxide during the catalytic reaction, n=a whole number from 1 to 8, is oxidised in the presence of a sulphoxide and/or a sulphide and the presence of iron salts or redox pairs of iron/copper or silver/copper salts, by means of an oxidising agent with a redox potential of Eo>+2 V vs. NHE, whereby the sulphoxide or sulphide has a catalytic function. The method permits the production of carbonyl compounds, in particular, (poly)aldehydes and (poly)ketones with high selectivity, whereby the formation of alcohols and carboxylic acids, dimerisation products and other by-products is reduced to a minimum or essentially prevented. The final products obtained find application as important intermediates and final products.
Abstract:
A functional group-selective hydrogenation catalyst is provided, which is capable of selectively hydrogenating an aliphatic carbon-carbon double bond, aliphatic carbon-carbon triple bond, aromatic formyl group or aromatic nitro group contained in an organic compound. The catalyst includes a carrier, and palladium and an organic sulfur compound supported jointly thereon.
Abstract:
The present invention relates to the preparation of nuclear-fluorinated aromatics by reacting, with a fluoride at 40 to 260° C., an aromatic compound substituted at the nucleus with halogen that is exchangeable for fluorine in the presence of at least one compound of the formula (I) where A, B, and Any have the meanings specified in the disclosure.
Abstract:
The present invention pertains to a process for sulfiding a catalyst composition comprising at least one hydrogenation metal component of Group VI and/or Group VIII of the Periodic Table, and an organic additive wherein the catalyst composition is first contacted with an organic liquid, followed by the catalyst being contacted with hydrogen and a sulfur-containing compound in the gaseous phase, wherein less than about 40%, preferably less than about 35%, more preferably less than about 25%, most preferably less than about 15%, of the sulfur present in the sulfided catalyst is added with the organic liquid. The process of the present invention makes it possible to use additive-containing catalysts without loss of activity in units which cannot effect gas phase start-up or are required to carry out a pressure test. The organic liquid may be a hydrocarbon with a boiling range of about 150-500null C., preferably gasoline, white spirit, diesel, gas oil, mineral lube oil, or white oil. The step of contacting the catalyst with hydrogen and a sulfur-containing compound may take place in one step at a temperature of about 150-450null C. It may also take place in two steps, with the first step being performed at a temperature which is lower than that of the second step, with the first step being carried out at a temperature of about 100-250null C. and the second step at a temperature of about 150-450null C.