Abstract:
Process for the monohalogenation of a benzene compound which has 2 or 3 CH.sub.2 OH substituents to obtain a product wherein one of the CH.sub.2 OH substituents is monohalogenated which comprises reacting an aqueous solution of the compound with hydrochloric or hydrobromic acid in the presence of a water immiscible organic solvent which is inert to the reactants, the partition coefficient of the compound in the aqueous/organic phases being greater, with respect to the aqueous phase, than the partition coefficient of the product. The novel compounds4-chloromethyl-2,3,5,6-tetrafluorobenzene methanol and4-bromomethyl-2,3,5,6-tetrafluorobenzene methanol are also disclosed.
Abstract:
The invention provides compounds of formula: ##STR1## wherein R.sup.1 represents hydrogen or halogen and R.sup.2 represents C.sub.1-8 alkyl or C.sub.1-8 haloalkyl, useful as insecticides and knockdown agents. The invention also provides compositions comprising them, methods of their use in controlling insects, and processes for their preparation.
Abstract:
Process for the production of 2,5-dimethyl-1,5-hexadiene by heating isobutene with a 1,1,2-trihalo ethylene in the vapor phase in the presence of a free-radical generator. The free-radical generator is preferably a peroxide and the reaction temperature in the range 200.degree.-600.degree. C. The product may be readily isomerized to 2,5-dimethyl-2,4-hexadiene, which is useful as an insecticide intermediate.
Abstract:
3-(Halogenovinyl- or propenyl-)-2,2-dimethyl cyclopropane-1-carboxylic acid esters, which are precursors of, or may themselves be, pyrethroid insecticides, are prepared by the reaction of certain halogenopentadienes with an alkyl diazoacetate in the presence of a catalyst which is a transition metal complex of certain chiral Schiff bases, which catalysts tend to increase the yield of preferred cis IR isomer relative to the other possible isomers.
Abstract:
Chiral Schiff bases, and transition metal complexes thereof, of formula: ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3, which may be the same ordifferent, are hydrogen, alkyl, aralkyl, aryl, alkaryl, a substituent containing a hetero atom, or two of R.sup.1, R.sup.2 and R.sup.3 together with the pyridine ring from fused system, R.sup.4 and R.sup.5 which may be the same or different, are hydrogen, lower alkyl, or, where n is 1, may with the pyridine ring to which CR.sup.4 R.sup.5 is attached form a fused system, R.sup.6 is hydrogen, alkyl, aralkyl, aryl or alkaryl, n is 0, 1 or 2 and J and K, which may be the same or different, are groups of the formulae: ##STR2## in which C* is an asymmetric carbon atom, and R.sup.7 and R.sup.8, which may be the same or different, are alkyl, aralkyl, aryl or alkaryl, or ##STR3## in which at least the ring carbon atom to which the iminyl nitrogen atom is attached is asymmetric, at least one of the carbon atoms adjacent the said ring carbon atom bears a hydroxyl group, R.sup.9 and R.sup.14, which may be the same or different, are hydrogen or lower alkyl, R.sup.10 is hydrogen, or lower alkyl, or together with R.sup.15 forms a divalent hydrocarbyl group, R.sup.11 is hydrogen, a sugar residue, or --CH.sub.2 OR.sup.15 in which R.sup.15 is hydrogen, lower alkyl or together with R.sup.10 forms a divalent hydrocarbon group, R.sup.12 is hydrogen or --CH.sub.2 OR.sup.15 in which R.sup.15 is hydrogen, or a lower alkyl, R.sup.13 is hydrogen, OR.sup.1, or a sugar residue, provided that both R.sup.12 and R.sup.13 are not hydrogen, m is 0, 1 or 2, p is 0 or 1 provided that m plus p is 0, 1, 2 or 3. The transition metal is for example copper (II), chromium (II), manganese (II), iron (II), cobalt (II), nickel (II) or palladium (II). The aforesaid complexes may be used as catalysts in the cyclopropanation of olefins by diazoacetates to form insecticide or insecticide precursors.
Abstract:
A process for the preparation of alkyl furans which comprises reacting furan with an alkyl halide in the presence of iron (III) oxide and an iron (II) halide or iron (III) halide as catalyst.
Abstract:
Cyanotetrachlorobenzenes, especially ortho- and para- dicyanotetrachlorobenzenes, are prepared by reacting in a liquid medium at 20.degree.-100.degree. C. a corresponding nitrotetrachlorobenzene with, in solution, an inorganic cyanide. Preferably the liquid medium is a two-phase water/water-immiscible organic solvent system, e.g. water/chloroform, a phase transfer catalyst is present and the inorganic cyanide is an alkali metal or alkaline earth metal cyanide.The compounds are useful chemical intermediates in the synthesis of, for instance, pesticidal compounds.
Abstract:
1,4-Dialkylbut-2-ene-1,4-diones are obtained by oxidizing a 2,5-dialkylfuran with an aqueous solution of an inorganic hypochlorite at a pH from 7 to 10.
Abstract:
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.
Abstract:
A process for the preparation of a polycyclic dye of Formula (1): ##STR1## by reacting a compound of Formula (2): ##STR2## with a benzofuranone of the Formula (3): ##STR3## wherein: Ring A is unsubstituted or is substituted by from one to three groups;Ring B is unsubstituted, apart from the nitro group, or is substituted by one or two further groups;R is H, optionally substituted alkyl or optionally substituted aryl; andZ is an oxyammonium group, and certain novel compounds of Formula (2) are disclosed.The process provides a convenient route to polycyclic dyes which are useful for the coloration of synthetic textile materials particularly polyesters.