摘要:
Process for preparing compounds according to formula (I) ##STR1## wherein R.sub.1 and R.sub.2 represent a hydrogen atom or a protective group and R.sub.3 represents a C.sub.1 -C.sub.10 alkyl or an aryl group, by oxidation of compounds according to formula (II) ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 have the above-mentioned meanings, in a two-phase system comprising:a) an organic phase including a 4-acylazetidinone compound (II) and an "onium" salt dissolved in a medium immiscible with water,b) an aqueous solution including an alkali or alkaline-earth metal salt of an organic or inorganic peracid.4-Acyloxyazetidinones (I) are useful intermediates in the synthesis of anti-bacterial compounds.
摘要:
There is disclosed a process for the biotechnological resolution, by enzymatic esterification of the corresponding racemic mixture of the S(+) and R(-) optical isomers of the oxazolidinonic compounds having formula (I): ##STR1## wherein R represents a, linear or branched, C.sub.1 -C.sub.8 alkyl group, which process is characterized in that, the racemic 3-alkyl-5-hydroxymethyl-oxazolidin-2-one derivative of formula (I) is reacted with an esterifying compound, selected from esters having formula (III): ##STR2## wherein R represents a, linear or branched, C.sub.1 -C.sub.10 alkyl or alkenyl group and R" represents a linear or branched, C.sub.1 -C.sub.4 alkyl, alkenyl group, a haloalkyl (chlorine, bromine) group or a diacyl glycerolic group or from acids having formula (IV):R'"--COOH (IV)wherein R'" represents a, linear or branched, C.sub.1 -C.sub.20 alkyl or alkenyl group or from anhydrides having formula (V): ##STR3## wherein R.sup.IV represents a, linear or branched, C.sub.1 -C.sub.6 alkyl group, in the presence of an enzyme, immobilized on a porous carrier, capable of giving rise selectively to the esterification reaction of the R(-) isomer, while leaving the S(+) isomer substantially unchanged, which latter is then separated according to known techniques.
摘要:
Biotechnological resolution by means of enzymatic transesterification of the relevant racemic mixture of the optical isomers of .alpha.-alkyl-substituted primary alcohols having the formula (I): ##STR1## wherein: R represents a linear or branched (C.sub.1 -C.sub.20)-alkyl or alkenyl group or an aryl group, also substituted or condensed with other groups, in particular a group of formula (II) or (III): ##STR2## wherein: R.sup.ii represents a (C.sub.1 -C.sub.8)-alkyl group, a (C.sub.1 -C.sub.4)-alkenyl group, an alkoxy, phenyl, phenoxy, benzoyl, or heterocyclic group;R.sup.iii represents a hydrogen or halogen atom;R.sup.iv represents a (C.sub.1 -C.sub.4)-alkyl group, and whereinR.sup.i represents a (C.sub.1 -C.sub.4)-alkyl group either equal to, or different from, R,in the presence of an enzyme either free or immobilized on a support capable of selectively causing the S isomer to be esterified, with the R isomer being left substantially unchanged, said isomers being then separated according to techniques known from the prior art. The process is used in the synthesis of antiinflammatory agents.
摘要:
A process is described for the preparation of hydrogen peroxide by the reaction of carbon monoxide, oxygen and water in an organic solvent immiscible with water, in the presence of a catalytic complex soluble in the organic solvent, deriving from the combination of a palladium salt, a non-coordinating organic or inorganic acid and a ligand capable of binding itself to the palladium atom, characterized in that said ligand is a mono or polydentate nitrogenated compound.
摘要:
A process for the production of bio-oil from solid urban waste, comprising the following steps: a) subjecting said solid urban waste to liquefaction, obtaining a mixture including an oily phase consisting of bio-oil, a solid phase and an aqueous phase; b) subjecting the aqueous phase obtained in the liquefaction step a) to fermentation, obtaining a fermented biomass; c) feeding the fermented biomass obtained in the fermentation step b) to the liquefaction step a). The bio-oil (or bio-crude) thus obtained can be advantageously used in the production of biofuels which can be used as such or mixed with other motor vehicle fuels. Alternatively, this bio-oil (or bio-crude) can be used as such (biocombustible) or mixed with fossil combustibles (combustible oil, coal, etc.) for the generation of electric energy or heat.
摘要:
A process for the production of bio-oil from solid urban waste, comprising the following steps: a) subjecting said solid urban waste to liquefaction, obtaining a mixture including an oily phase consisting of bio-oil, a solid phase and an aqueous phase; b) subjecting the aqueous phase obtained in the liquefaction step a) to fermentation, obtaining a fermented biomass; c) feeding the fermented biomass obtained in the fermentation step b) to the liquefaction step a). The bio-oil (or bio-crude) thus obtained can be advantageously used in the production of biofuels which can be used as such or mixed with other motor vehicle fuels. Alternatively, this bio-oil (or bio-crude) can be used as such (biocombustible) or mixed with fossil combustibles (combustible oil, coal, etc.) for the generation of electric energy or heat.
摘要:
Process for the solubilization of polymeric material deposited on a porous medium, which comprises putting said polymeric material in contact with an aqueous composition comprising: (a) a catalyst selected from: (a1) a complex having general formula (I), Fe++(L)n(Y)s, L being a binder selected from those having general formula (II), wherein X═CH, N, (a2) a hydrosoluble cobalt2+ salt, preferably cobalt acetate; (b) an oxidizing agent selected from: (b1) hydrogen peroxide, (b2) MHSO5, wherein M is an alkaline metal, preferably potassium; with the constraint that the catalyst (a1) can only be used in the presence of the oxidizing agent (b1) and the catalyst (a2) can only be used in the presence of the catalyst (b2).
摘要:
A process for the conversion of lignin to liquid hydrocarbons comprising: (1) hydrogenolyzing a lignin in the presence of at least one hydrogenolysis catalyst, at a temperature ranging from 250° C. to 350° C., preferably ranging from 290° C. to 320° C., to obtain depolymerized lignin; and (2) hydrodeoxygenating said depolymerized lignin in the presence of a hydrodeoxygenating catalyst to obtain a mixture of liquid hydrocarbons. The resultant liquid hydrocarbons can be used as such (biofuels) for the production of reformulated gasolines, or they can be used for the production of gasolines or oils by conventional refining processes.
摘要:
The cultivation of heterotrophic and phototrophic micro-organisms is integrated for the production of bio-oil for biofuels, wherein the overall algal suspension produced is first thickened, with recirculation of the excess water to cultivation containers, and then thermally treated at a high temperature. After cooling, a bio-oil phase is recovered together with a suspension rich in soluble carbohydrates and proteins which forms a nutritional/energy source for heterotrophic micro-organisms.
摘要:
The invention relates to a process for the hydroxylation of aromatic hydrocarbons by direct oxidation with hydrogen peroxide. The process is carried out in the presence of a catalyst comprising:iron, administered as inorganic salt;iron ligand, consisting of carboxylic acids of ether-aromatic compounds containing nitrogen, in particular pyrazin-2-carboxylic acid and derivatives;acidifying agent, especially trifluoracetic acid, and a solvent system comprising an organic phase consisting of a substrate and acetonitrile and an aqueous phase containing the catalyst and hydrogen peroxide.