Shell Oil Comapny

Shell Internationale Research Maatschappij, B.v.

Petrus A Kramer

Pieter A Verbrugge

Helena Austermuhle-Bertola

Johannes Van Berkel

Robert Van Helden

Hendrik C Kelderman

Marinus J Van Den Brink

Nitrophenylalkanols are prepared by hydroxyalkylation of nitrotoluene(s) by the reaction with an aldehyde in the presence of a solid catalyst prepared by depositing an alkali metal compound on an alumina support.

Process for the preparation of nitrophenylalkanols

Novel compounds of the formula I ##STR1## in which each of Y.sup.1 and Y.sup.2 independently represents a fluorine, chlorine or bromine atom and each of R.sup.1 and R.sup.2 independently represents a hydrogen atom or an alkyl group having up to 10 carbon atoms, or R.sup.1 and R.sup.2 together represent an alkylene group having from 2 to 5 carbon atoms, may be converted by the action of base into the corresponding dihalovinylcyclopropane carboxylic acids.

Process for the preparation of

When the reaction of aldehydes with alkali metal trihaloacetates is carried out in the presence of a highly polar aprotic solvent (DMF, DMSO), novel organic alkali metal carbonates, which are precursors of pyrethroid insecticides, are formed in high yields and at a high rate. Novel sulfonates and dihalophosphites, derived from these carbonates have also been claimed.

Trihalomethylation of aldehydes

Process for the preparation of dihalovinylcyclopropane carboxylic acid

Novel compounds of the formula I ##STR1## in which each of Y.sup.1 and Y.sup.2 independently represents a fluorine, chlorine or bromine atom and each of R.sup.1 and R.sup.2 independently represents a hydrogen atom or an alkyl group having up to 10 carbon atoms, or R.sup.1 and R.sup.2 together represent an alkylene group having from 2 to 5 carbon atoms, may be converted by the action of base into the corresponding dihalovinylcyclopropane carboxylic acids which are intermediates for preparing known pyrethroid insecticides.

Oxabicyclo[3.1.0]hexan-2-ones

A process for the preparation of dihalovinyl compounds of the formula ##STR1## wherein each Hal is fluorine, chlorine or bromine, R.sup.1 is an optionally substituted hydrocarbyl group, R.sup.2 is a methyl group or a hydrogen atom, or R.sup.1 and R.sup.2 together with the carbon atom to which they are attached form cycloalkylidene group, which process comprises treating a trihalo compound of the formula ##STR2## wherein Hal, R.sup.1 and R.sup.2 have the above meanings and R.sup.3 is a hydrogen atom or ##STR3## in which M is an alkali atom, with PHal.sub.3.

Preparation of dihalovinyl compounds

The novel dihalomethylenelactone of formula (I) can be prepared by the trihalomethylation of an anhydride of formula (II). Reaction of compound (II), wherein R.sub.1 =R.sub.2 =methyl, with CBr.sub.3 COONa in DMF gave at -25.degree. C. the dibromovinyllactone and with CCL.sub.3 COONa in DMF at 0.degree. C. the dichlorovinyllactone. ##STR1## X.sub.1, X.sub.2 and X.sub.3 are halogen atoms and R.sub.1 and/or R.sub.2 are hydrogen atoms and/or alkyl groups with 1-10 carbon atoms;

Dihalomethylenelactone pyrethroid intermediates

Conversion of esters (R.sup.1)(R.sup.2)C(C Hal.sub.3)OX, X being-P Hal.sub.2, --C(O)OR.sup.3 or ##STR1## R.sup.1, R.sup.3 and R.sup.4 being optionally substituted hydrocarbyl groups and R.sup.2 methyl or hydrogen, with zinc in acetic acid gives a very high yield of a dihalovinyl compound (R.sup.1)(R.sup.2)C.dbd.C Hal.sub.2, e.g., of the ethyl ester of the parent acid of pyrethroid insecticides.

Process of preparing dihalovinyl compounds

Cyclopropyl dihalo phosphites

Preparation of novel alkyl 2,2-dihalovinylcyclopropylacetates (intermediates in the preparation of insecticides) by reaction of a phosphine with a compound generating a dihalocarbene and reaction of the product resulting therefrom with an alkyl formylcyclopropylacetate, both reactions being carried out in a solvent.

1R, Cis 2,2-dihalovinyl-3,3-dimethylcyclopropylmethanol and ester

Isolation of cis acids of the formula ##STR1## wherein each of the groups X.sup.1 and X.sup.2 represents a fluorine, chlorine or bromine atom or a hydrocarbyl group, from a mixture of cis and trans acids of this formula, by idolactonization, forming novel cis-lactones of the formula ##STR2## isolation of these cis-lactones and reduction thereof to the said cis acids. The process may be used for the isolation of cis precursors to insecticides from mixtures with their trans isomers.

Cis-lactone pyrethroid intermediates

Trihalocyclopropyl carbonates

2-Formyl-3,3-dimethylcyclopropylacetic acid is prepared by ozonolysis of 3-acetyl-6,6-dimethylbicyclo[3.1.0]-2-hexene followed by reductive cleavage of the ozonolysis product thus formed. The 3-acetyl-6,6-dimethylbicyclo[3.1.0]-2-hexene is prepared by contacting 2-(2-acetyl-3-oxobutyl)-3,3-dimethylcyclopropanecarbaldehyde with a base in the presence of a solvent.

Preparation of 2-formyl-3,3-dimethylcyclopropaneacetic acid

The invention relates to 2-(2,2-dihalovinyl)-3,3-dimethylcyclopropylacetones which are intermediates for the preparation of pyrethroids which have good insecticidal properties.

2-(2,2-Dihalovinyl)-3,3-dimethylcyclopropylacetone pyrethroid

New 2-(2,2-dihalovinyl)-3,3-dimethylcyclopropane derivatives of the formula ##STR1## wherein each Hal is a halogen atom and R is dimethoxyethyl, 2-acetyl-3-oxobutyl, 2-methoxycarbonylpropyl or 2-acetyl-2-hydroxy-3-oxobutyl, are useful chemical intermediates for the preparation of pesticidally active cyclopropanecarboxylates.

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Amsterdam, Netherlands

Petrus A Kramer