摘要:
A process for preparing a compound of formula I: ##STR1## wherein R.sub.1 represents a hydroxy protecting group and R.sub.2 represents a carboxy protecting group, which comprises:hydrolyzing a compound of formula II ##STR2## wherein R.sub.1 and R.sub.2 are as defined above and R represents an alkyl, alkenyl or phenylalkyl group having from 1 to 18 carbon atoms, in the presence of an enzyme capable of selectively hydrolyzing the ester group of the 2-substituent thereof.
摘要:
A process is disclosed for preparing N-methylcarbamate of methylthioacetaldoxime, characterized in that an aqueous suspension of methylthioacetaldoxime is additioned, in one step only, with gaseous phosgene and aqueous methylamine in the presence of an inorganic alkaline base substantially at room temperature and pressure.The product obtained, known commercially as "Methomyl", is an important active principle in the field of insecticides.
摘要:
Process for preparing a catalyst for the oxidation of methanol to formaldehyde, comprising reacting iron powder and molybdenum trioxide in a Mo/Fe ratio from 1.5 to 5 in an aqueous suspension at temperatures from 20 to 100° C., and subsequently, optionally simultaneously, oxidizing the mixture with an oxidizing agent in a quantity equal to, or greater than the quantity required for the oxidation of the ferrous ion to ferric ion and to oxidize the molybdenum to the valence state 6.
摘要:
The mono-methallyl ether of pyrocatechin of formula (I): ##STR1## is prepared by reacting pyrocatechin of formula (II): ##STR2## with a methallyl halide of formula (III): ##STR3## in a homogeneous dissolving medium, e.g., alcohols, aliphatic polyalcohols and monoethers thereof, or water, in the presence of an organic or inorganic base.The mono-methallyl ether of pyrocatechin is used as an intermediate for organic syntheses and, in particular for synthesizing the product of formula (IV); ##STR4## which is marketed under the tradename "Carbofuran" and is a compound which is the active principle in soil insecticides of different overall compositions which are available on the market.
摘要:
Carboxylable substrates i.e., ketones, esters, nitroparaffins and nitriles, containing activated hydrogen atoms are carboxylated by reaction with alkaline phenates and CO.sub.2 in at least one hydrocarbon solvent selected from aliphatic, alicyclic, aromatic and alkyl-aromatic hydrocarbon solvents.
摘要:
Catalysts for oxidation of methanol to formaldehyde, comprising a catalytic mixtures of Fe2(MoO4)3/MoO3, wherein the Mo/Fe atomic ratio ranges from 1.5 to 5, and a compound of cerium molybdenum and oxygen in a quantity from 0.1 to 10% by weight expressed as cerium.
摘要:
Substituted benzofuran derivatives of the formula (I): ##STR1## wherein one of R.sub.1 and R.sub.2 is hydrogen or halogen and the other is, independently, an amino group or a C.sub.2 -C.sub.4 alkanoyl amino group; R.sub.3 is hydrogen; a linear or branched C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy or C.sub.2 -C.sub.4 alkoxycarbonyl group; halogen; or phenyl unsubstituted or substituted by a C.sub.1 -C.sub.4 alkyl group; A is a group --(CH.sub.2).sub.n -Het wherein Het is an optionally substituted heteromonocyclic or heterobicyclic ring containing one or two nitrogen atoms, and n is zero or an integer of 1 to 3; and the symbol ..... represents a single or double bond; may be prepared by a process comprising reacting a compound of formula II: ##STR2## in which L is a leaving group and R.sub.4 is hydrogen or a carboxy protecting group, with a compound of formula III;R'.sub.3 --C.dbd.C--R'.sub.3 IIIto obtain a compound of formula IV; ##STR3## which is then cyclized to obtain a compound of formula V; ##STR4## which is reacted with a compound of formula VI;H.sub.2 N--A VI.
摘要:
A process is disclosed for the carboxylation of organic substrates or reactants containing at least one active hydrogen atom by reaction with CO.sub.2 and alkaline phenates in an organic medium, characterized in that the reaction is conducted in the presence of simple or substituted alkaline phenates in at least an aprotic medium which is at least a partial solvent for the phenate, and selected from the class consisting of cyclic ethers, aliphatic, cycloaliphatic and heterocyclic tertiary amines, and cyclic sulphones, and at temperatures between about 40.degree. and 60.degree. C. The alkaline phenate is selected from the class consisting of the Li, Na, K salts of the phenols of the general formula: ##STR1## WHEREIN R is hydrogen or an alkyl or an alkoxy group, linear or branched, having up to 20 carbon atoms, or a phenyl group, n varies from 1 to 5, and M is the alkali metal. The starting organic substrate or reactant is selected from the class consisting of ketones, esters, nitroparaffins and nitriles. The alkaline phenate may be prepared "in situ" from the corresponding phenol and alkaline hydroxide with azeotropic elimination by means of solvent of the water thus formed.
摘要:
Process for preparing a catalyst for the oxidation of methanol to formaldehyde, comprising reacting iron powder and molybdenum trioxide in a Mo/Fe ratio from 1.5 to 5 in an aqueous suspension at temperatures from 20 to 100° C., and subsequently, optionally simultaneously, oxidizing the mixture with an oxidizing agent in a quantity equal to, or greater than the quantity required for the oxidation of the ferrous ion to ferric ion and to oxidize the molybdenum to the valence state 6.
摘要:
Catalysts for oxidation of methanol to formaldehyde, comprising a catalytic mixtures of Fe2(MoO4)3/MoO3, wherein the Mo/Fe atomic ratio ranges from 1.5 to 5, and a compound of cerium molybdenum and oxygen in a quantity from 0.1 to 10% by weight expressed as cerium.
摘要翻译:用于将甲醇氧化成甲醛的催化剂,其包含Fe 2 O 3(MoO 4 N 3)3 MoO 3的催化混合物 >其中Mo / Fe原子比为1.5〜5,铈钼和氧的化合物为0.1〜10重量%,表示为铈。