摘要:
A halogenated hydrocarbon having the general formula: ##STR1## wherein Y represents fluorine, chlorine, bromine or --(CF.sub.2).sub.m W, R represents hydrogen or lower alkyl, R.sup.1 represents lower alkyl, X represents chlorine, bromine or iodine, W represents hydrogen, fluorine or chlorine and m is 1 or 2, is prepared by heating a compound having the general formula: ##STR2## wherein R, R.sup.1, X, Y, W and m have the meanings given above and Z represents chlorine, bromine or iodine, in a polar aprotic solvent together with an alkanolamine, optionally in the presence of a copper salt.
摘要:
2-Benzyloxyalkyl halophenones of the formula (3): wherein X1 and X2 are each independently H, Cl or F, provided that at least one of X1 and X2 is Cl or F; one of R3 and R4 is H and the other is optionally substituted benzyloxy; and R5 is an unsubstituted alkyl, preferably a C1-6 alkyl group. The compounds are useful as intermediates for preparing 2-hydroxyalkyl halophenones.
摘要:
A process is provided for the preparation of compounds of Formula (1): wherein X1 and X2 are each independently H, Cl or F, provided that at least one of X1 and X2 is Cl or F; one of R1 and R2 is H and the other is OH; and R5 is an unsubstituted alkyl, preferably a C1-6 alkyl, group. The process comprises condensing a 2-chloroalkanoic acid with an optionally substituted benzyl alcohol to form a 2-(optionally substituted benzyloxy) alkanoic acid, converting the condensation product to the corresponding acid chloride and then either reacting the acid chloride with a compound of the Formula (2) in the presence of a source of copper (I) to give a compound of Formula (3) wherein one of R3 and R4 is H and the other is optionally substituted benzyloxy; or reacting the acid chloride with a compound of Formula (4): A—NH—B wherein A and B independently represent substituted alkyl, alkoxy, aryl or oxyaryl groups, or are linked to form a heterocyclic ring to form an amide, and then reacting the amide with a compound of Formula (2) to give a compound of Formula (3). The optionally substituted benzyl group from the compound of Formula (3) can removed by hydrogenation.
摘要:
A process for purifying elemental phosphorus that contains antimony using an oxidizer, such as hydrogen peroxide, peroxymonosulfate, peroxydisulfate, or a hypochlorite, in a two phase system containing water and phosphorus as the two liquids. A purified elemental phosphorus having 200 ppb or less antimony content.
摘要:
A process for the separation of at least one isomer from a mixture of isomers of a tetrahydropyran-2-one, having at least two chiral centers which comprises selective reaction of at least one isomer with a reagent catalyzed by a hydrolase enzyme whereby at least one isomer is preferentially converted into a distinct chemical species from the other isomers so that it is susceptible of separation by an appropriate chemical or physical separation process in which the tetrahydropyran-2-one is of Formula (1): ##STR1## wherein: Z is --H or a protecting group susceptible of reaction with the reagent under the influence of the enzyme; andY is formyl or protected formyl.
摘要:
A process for the separation of at least one isomer from a mixture of isomers of a tetrahydropyran-2-one, having at least two chiral centres, which comprises selective reaction of at least one isomer with a reagent catalysed by a hydrolase enzyme whereby at least one isomer is preferentially converted into a distinct chemical species from the other isomers so that it is susceptible of separation by an appropriate chemical or physical separation process in which the tetrahydropyranone is of Formula (1): ##STR1## wherein: Z is --H or a protecting group susceptible of reaction with the reagent under the influence of the enzyme; andY is optionally substituted hydrocarbyl.
摘要:
3-(2'-chloro-3',3',3'-trifluoropropenyl)-2,2-dimethylcyclopropane-1-carboxylic acid esters are prepared by dehydrohalogenation of the corresponding 3-(2',2'-dichloro-3',3',3-trifluoropropyl) compounds by reaction with an alkali metal carbonate in a polar aprotic solvent. The products are intermediates in the preparation of pyrethroid insecticides or are themselves insecticides.
摘要:
3-Halogenoethyl- or propyl-2,2-dimethylcyclopropane carboxylic acid esters, which are intermediates in the preparation of synthetic pyrethroids, are prepared by the reaction of certain halogenopentenes or hexenes with a diazoacetic ester in the presence of a catalyst which is metallic copper or a copper (II) salt, a rhodium (II) salt of a carboxylic acid or a transition metal complex of certain chiral Schiff bases. By the use of the latter class of catalysts the yield of preferred cis IR isomer may be increased relative to the other possible isomers.
摘要:
Improved elastomers are made by cross-linking a polyurethane through double bonds derived from a diisocyanato bicyclo octene used together with a linear prepolymer to make the polyurethane.