Fisons Ltd.

Derek Baldwin

Peter S Gates

John Gillon

Carol A Wilson

The invention provides herbicidally-active 2,3-dihydro-5-cyanobenzofurans of the formula: ##STR1## (wherein: R.sup.1 and R.sup.2 together represent .dbd.O or R.sup.1 represents hydrogen and R.sup.2 represents hydrogen, hydroxy, alkoxy, acyloxy, alkoxycarbonyloxy, alkylthiocarbonyloxy, halogen, isothiocyanato, amino, alkylamino, dialkylamino, arylamino, acylamino, alkoxycarbonylamino, alkylthiocarbonylamino, N-bonded heterocyclyl, cyano or alkylthio; R.sup.3 and R.sup.4 together represent alkylene or each represent hydrogen or alkyl; and R.sup.5, R.sup.6 and R.sup.7, which may be the same or different, each represent hydrogen, halogen, alkyl, alkoxy, acyl or cyano), processes for their preparation and herbicidal compositions containing them. ,

Herbicidal 5-cyano-2,3-dihydro-benzofuran-2-ones

The invention provides herbicidally-active 2,3-dihydro-5-cyanobenzofurans of the formula: ##STR1## (wherein: R.sup.1 and R.sup.2 together represent .dbd.O or R.sup.1 represents hydrogen and R.sup.2 represents hydrogen, hydroxy, alkoxy, acyloxy, alkoxycarbonyloxy, alkylthiocarbonyloxy, halogen, isothiocyanato, amino, alkylamino, dialkylamino, arylamino, acylamino, alkoxycarbonylamino, alkylthiocarbonylamino, N-bonded heterocyclyl, cyano or alkylthio; R.sup.3 and R.sup.4 together represent alkylene or each represent hydrogen or alkyl; and R.sup.5, R.sup.6 and R.sup.7, which may be the same or different, each represent hydrogen, halogen, alkyl, alkoxy, acyl or cyano), processes for their preparation and herbicidal compositions containing them.

5-Cyano-2,3-dihydrobenzofurans useful as herbicides

The invention provides herbicidally-active sulphonates of the formula ##STR1## wherein X represents a group --CHR.sup.3 --OR.sup.4 and Y represents a group --OR.sup.5, or X and Y together represent a group --CHR.sup.3 --O-- or a group --CHR.sup.3 --O--Z--O--, the free oxygen atom of which is attached to the benzene ring; R.sup.1, R.sup.2 and R.sup.3, which may be the same or different, each represent hydrogen or C 1 to 6 alkyl, or R.sup.1 and R.sup.2 together or R.sup.2 and R.sup.3 together form a C 3 to 6 alkylene chain; R.sup.4 and R.sup.5, which may be the same or different, each represent hydrogen, C 1 to 6 alkyl, C 2 to 6 alkenyl, C 2 to 6 alkynyl, phenyl, a group --C(.dbd.O)R.sup.10 or a group --SO.sub.2 R.sup.11 ; R.sup.6, R.sup.7 and R.sup.8, which may be the same or different, each represent hydrogen, C 1 to 6 alkyl, halogen, cyano, C 2 to 6 carboxylic acyl, or C 1 to 4 alkoxy; R.sup.9 represents C 1 to 6 alkyl, phenyl or C 7 to 10 phenylalkyl (each of which may be unsubstituted or substituted by one or more chlorine or bromine atoms, C 1 to 4 alkyl groups, C 1 to 4 alkoxy groups or nitro groups), C 5 to 7 cycloalkyl, C 1 to 4 alkylamino, or dialkylamino wherein each alkyl moiety has from 1 to 4 carbon atoms; R.sup.10 represents C 1 to 6 alkyl or alkoxy, C 2 to 6 alkenyl or alkenyloxy, C 2 to 6 alkynyl or alkynyloxy, phenyl, phenoxy, phenylamino, C 1 to 6 alkylamino or dialkylamino wherein each alkyl moiety has from 1 to 6 carbon atoms, each of the groups which R.sup.10 may represent being unsubstituted or substituted by one or more halogen atoms or C 1 to 4 alkoxy groups; R.sup.11 represents C 1 to 6 alkyl, phenyl, C 1 to 6 alkylamino or dialkylamino each of the alkyl moieties thereof having from 1 to 6 carbon atoms, each of the groups which R.sup.11 may represent being unsubstituted or substituted by one or more halogen atoms or C 1 to 4 alkoxy groups; Z represents a group of formula --S(.dbd.O)n, --CR.sup.12 R.sup.13 or --P(.dbd.Q)(OR.sup.14)--; n represents 1 or 2; R.sup.12 and R.sup.13, which may be the same or different, each present hydrogen, C 1 to 6 alkyl or alkoxy, C 2 to 6 alkenyl or alkynyl, phenyl, phenoxy, cyano or (C 1 to 6 alkoxy)carbonyl, or R.sup.12 and R.sup.13 together represent an oxygen atom, a sulphur atom, a C 3 to 6 alkylene chain or a C 1 to 6 alkylimino group or a phenylimino group; and R.sup.14 represents C 1 to 6 alkyl; and Q represents oxygen or sulphur, together with processes for their preparation and herbicidal compositions containing them.

Certain herbicidal sulfonates and sulfamates

Pyrogallol is prepared by (A) reacting a halo compound of formula ##STR1## where X represents Br or I, R.sup.1 represents hydrogen, secondary or tertiary alkyl of up to 10 carbon atoms, carboxy or alkoxycarbonyl of 2-5 carbon atoms and R.sup.2 represents hydrogen or alkyl of 1-4 carbon atoms, with an alkali metal alkoxide of formula ROM where M represents an alkali metal and R represents alkyl of 1-4 carbon atoms, to replace each X by OR, and then (B) dealkylating each OR and each OR.sup.2 where R.sup.2 represents alkyl of 1-4 carbon atoms and removing the R.sup.1 group where this is not hydrogen.

Process for preparing pyrogallol

The invention provides herbicidally-active sulphonates of the formula ##STR1## wherein X represents a group --CHR.sup.3 --OR.sup.4 and Y represents a group --OR.sup.5, or X and Y together represent a group --CHR.sup.3 --O-- or a group --CHR.sup.3 --O--Z--O--, the free oxygen atom of which is attached to the benzene ring; R.sup.1, R.sup.2 and R.sup.3, which may be the same or different, each represent hydrogen or C 1 to 6 alkyl, or R.sup.1 and R.sup.2 together or R.sup.2 and R.sup.3 together form a C 3 to 6 alkylene chain; R.sup.4 and R.sup.5, which may be the same or different, each represent hydrogen, C 1 to 6 alkyl, C 2 to 6 alkenyl, C 2 to 6 alkynyl, phenyl, a group --O(.dbd.O)R.sup.10 or a group --SO.sub.2 R.sup.11 ; R.sup.6, R.sup.7 and R.sup.8, which may be the same or different, each represent hydrogen, C 1 to 6 alkyl, halogen, cyano, C 2 to 6 carboxylic acyl, or C 1 to 4 alkoxy; R.sup.9 represents C 1 to 6 alkyl, phenyl or C 7 to 10 phenylalkyl (each of which may be unsubstituted or substituted by one or more chlorine or bromine atoms, C 1 to 4 alkyl groups, C 1 to 4 alkoxy groups or nitro groups), C 5 to 7 cycloalkyl, C 1 to 4 alkylamino, or dialkylamino wherein each alkyl moiety has from 1 to 4 carbon atoms; R.sup.10 represents C 1 to 6 alkyl or alkoxy, C 2 to 6 alkenyl or alkenyloxy, C 2 to 6 alkynyl or alkynyloxy, phenyl, phenoxy, phenylamino, C 1 to alkylamino alylamino or dialkylamino wherein each alkyl moiety has from 1 to 6 carbon atoms, each of the groups which R.sup.10 may represent being unsubstituted or substituted by one or more halogen atoms or C 1 to 4 alkoxy groups; R.sup.11 represents C 1 to 6 alkyl, phenyl, C 1 to 6 alkylamino or dialkylamino each of the alkyl moieties thereof having from 1 to 6 carbon atoms, each of the groups which R.sup.11 may represent being unsubstituted or substituted by one or more halogen atoms or C 1 to 4 alkoxy groups; Z represents a group of formula

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Cambridge, United Kingdom

Derek Baldwin