IL35165A - 2-alkyl-glycerol derivatives,their preparation and herbicidal compositions containing them - Google Patents

Description

jnaan , 1"IJ_»VA!-7'P R-2 7W ηπ7 η 2-Alkyl-glycerol derivatives, their preparations and herbicide! compositions containing them BHELL INTERNATIONALS RESEARCH HAATSCHAPPIJ N.V. 35165/2 ~2~ This invention relates to 2-alkyl glycerol derivatives which are biologically active, in particular, "possessing! herbicidal plant growth regulant end fungicidal properties.

Accordingly, the present invention provides 2-alkyl glycerol derivatives having the general formula;- CH20Y I II wherein R represents an alk l group of 1-6 carbon atoms; R^ and Rg each individually represents a hydrogen atom, an alkyl group of 1-6 carbon atoms optionally substituted by a halogen atom or a phenyl group, an alkoxy group of 1-6 carbon atoms, a phenyl group optionally substituted by one or more halogen atoms or by an alkyl or alkoxy group of 1-6 carbon atoms or by a ni ro group, or a furyl pyridyl or phenoxyalkyl group, optionally substituted by one or more halogen atoms or 1 and g together represent a polyrnethylene group, or ^ and Rg together with the carbon atom to which they are bound represent a carbonyl group; and Y represents an alkenyl group of up to 6 carbon atoms or a phenyl group, a benzyl group optionally substituted in the benzene ring. by one or more halogen atoms or by a metl or phenyl group, or a furfuryl or pyridylmethyl group, or a oyclohexylmethyl, benzoyl or N- phenylcarbamoyl group„ By reason of their high level of biological activity 35165/2 -3~ 4-^enzyloxymethyl-2,2-dimethyl-4-n-propyl-l, 3-dioxolane.; 4-benzyloxymethyl-2 , 2-dimeth l-4-ethyl-l, 3- dioxolane; -benzyloxy-5-methyl-2-phenyl-l, 3-dioxane; 2-benzyloxymethyl-2-methyl-l,4-dioxaspiro^ ,5/ decane ; 3~^enzyloxy-3-methyl-l,5-dioxaspiro<£5o57 undecane.

It will be appreciated that many of the 2-alkyl glycerol derivatives of the invention may exhibit geometrical and/or optical isomerism.^ The individual isomers of these compounds together with isomeric mixtures thereof are included within the scope of the present invention.

The invention includes also a process for the preparation of . 2-alkyl glycerol derivatives of formula I, which comprises reacting the corresponding monohydroxyjderiyative with an organohalo derivative of formula:- Hal-Y III wherein Y represents an optionally substituted hydrocarbyl or acyl group and Hal represents a halogen, preferably chlorine, atome The hydroxy derivative is, preferably used in the form of a salt, suitably the salt of an alkali metal, such as sodium, and the reaction is, preferably carried out in an organic solvent, such" as toluene. When the group Y in Formula I represents a carbamoyl group the halo compilenyl pound may be replaced by tan oasasuaia isocyanate and the reaction 35165/2. is, preferably, carried out in the presence of an organic base, for example, a tertiary amine, such as triethylaminee •In certain cases, for example, when the group .Y is a phenyl or furfuryl group, it is more convenient to use an alternative process which comprises reacting an appropriate halopropane derivative with a salt of formula MetO-Y IV wherein Met represents an alkali metal, suitably sodium, atom. This reaction is, preferably, carried out in a polar organio solvent, such as dimethyl sulphoxide. , 35165/2 The compounds of formula I may also be prepared by reacting the corresponding diol with a carbonyl compound of formula or a acetal or ketal derived from euch a carbonyl compound, in the presence of an acid, suitably an inorganic acid, such as hydrochloric acid or an arylsulphonic aoid, such as p_-toluenejmlphonlc acid. The reaction is, preferably, carried out in an aromatic hydrocarbon, for example, benzene or toluene, as solvent* The compounds of formula I, wherein and R2 together with the carbon atom to which they are bound represent a carbonyl group, are obtained by reacting the corresponding diol with a dialkyl carbonate, suitably, diethyl carbonate* in the presence of a base, suitably an alkali metal alkox de, such as sodium ethoxide.

As mentioned above, the 2-alkyl glycerol derivatives of the invention exhibit herbioidal and plant growth regulant properties and the invention, therefore, includes biologically active compositions comprising a carrier or a surface-active agent, or both a carrier and a surface-active agent, and as active ingredient at least one 2-alkyl glycerol derivative of the Invention.

■ The term 'carrier' as used herein means a material, which may be i organio or organic and of synthetic or natural origin, with which the active compound is mixed or formulated to facilitate its application to the plant seed, soil or other object to be treated, or its storage, transport or handling. The carrier may be a solid or a fluid. Any of the material usually applied in formulating pesticides may be used-as carrier.

Suitable solid carriers are natural and synthetic clays and silicates, for example, natural silicas, such as diatomaceous earths; magnesium silicates, for example, talcs; magnesium aluminium silicates, for example, attapulgites and vermiculites; aluminium silicates, for example, kaolinites, montmorillonites and micas; calcium carbonates; calcium sulphate; synthetic hydrated silicon oxides and synthetic calcium or aluminium silicates; elements, such as, for example, carbon and sulphur; natural and synthetic resins, such: as, for example, coumarone resins, polyvinyl chloride and styrene polymers and copolymers; solid polychlorophenols; bitumen; waxes, such as, for example, beeswax, paraffin wax, and chlorinated mineral waxes; solid fertilizers, for example, super-phosphates.

Examples of suitable fluid carriers are water, alcohols, such as, for example, isopropanol, glycols; ketones, such as for example, acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethers; aromatic hydro-carbons, such as, for example, benzene, toluene and xylene; petroleum fractions, such as* for example, kerosine, light mineral oils; chlorinated hydrocarbons, such as, for example, carbon tetrachloride, perchloroethylene, trlchloroethane, including liquefied normally vaporous .gaseous compounds. Mixtures of different liquids are often suitable.

The surface-active agent may be an emulsifying agent or a dispersing agent or a wetting agent; it may be non-ionic or ionic. Any of the surface-active agents usually applied in formulating herbicides or insecticides may be used. Examples of suitable surface-active agents are the sodium or calcium salts of polyacrylic acids and lignin sulphonic acids; the condensation products of fatty acids or aliphatic amines or amides containing at least 12 carbon atoms in the molecule with ethylene oxide and/or propylene oxide; fatty acid esters of glycerol, sorbitan, sucrose or pentaerythritol; condensates of these with ethylene oxide and/or propylene oxide; condensation products of fatty alcohols or alkyl phenols, for example, p-octylphenol or p-octylcresol, with ethylene oxide and/or propylene oxide; sulphates or sulphonates of these condensation products; alkali or alkaline earth metal salts, preferably sodium salts, of sulphuric or sulphonic acid esters containing at least 10 carbon atoms in the molecule, for example, sodium lauryl sulphate, sodium secondary alkyl sulphates, sodium salts of sulphonated castor oil, and sodium alkylaryl sulphonates, such as sodium dodecylbenzene sulphonate; and polymers of ethylene oxide and copolymers of ethylene oxide and propylene oxide.

The compositions of the invention may be formulated as wettable powders, dusts, granules, solutions, emulsifiable concentrates, emulsions, suspension concentrates and aerosols. Wettable powders are usuflly compounded to contain 25, 50 or 7 #w of toxicant and usually contain, in addition to solid carrier, j5-10#w of a dispersing agent and, where necessary, 0-lO^w of stabilizer(s) and/or additives, such as penetrants or stickers. Dusts are usually formulated as a dust concentrate having a similar composition to that of a wettable powder, but without a dispersant, and are diluted in the field with further solid carrier to give a composition usually con- taining - -10#w of toxicant. Granules are usually prepared to have a size between lOOand 100 BS mesh, and may be manufactured by agglomeration or impregnation techniques. Generally, granules will contain ½-25#w toxicant and 0-10#w of additives, such as stabilizers, slow release modifiers and binding agents. Emulsifiable concentrates usually contain, In addition to -the solvent and, when necessary, co-solvent, - 50#w/v toxicant, 2-20#w/v emulsifiers and 0-20#w/v of appropriate additives, such as stabilizers, penetrants and corrosion inhibitors. Suspension concentrates are compounded so as to obtain a stable, non-dedimenting, flowable product and usually contain 10-75#w toxicant, 0.5-15#w dispersing agents, 0.1-10#w of suspending agents, such as protective colloids and thixotropic agents, 0-10#w of appropriate additives, such as defoamers, corrosion inhibitors, stabilizers, penetrants and stickers, and as carrier, water or an organic liquid, in which the toxicant is substantially insoluble; certain organic solids or inorganic salts may be dissolved in the carrier to assist in preventing sedimentation or as ant 1-freeze gents for water.

The compositions of the invention may contain other ingredients, for example, protective colloids, such as gelatin, glue, casein, gums, cellulose. ethers, and polyvinyl alcohol; thixotropic agents, e.g. bentonites, sodium polyphosphates; stabilizers, such as ethylene diamine tetra-acetic acids, urea, triphenyl phosphate; and stickers, for example, non-volatile oils.

Aqueous dispersion and emulsions, for example, compositions obtained by diluting a wettable powder or an emulsifiable concentrate according to the invention with water, also lie within the scope of the present invention.

The said emulsions may be of the water-in-oil or of the 011-in-water type, and may have a thick "rnayonnaise"-like consistency.

The 2-alkyl glycerol derivatives of the present invention are of interest as herbicides and particularly as selective herbicides for pre-emergence application to control grass weeds. The invention includes, therefore, within its scope a method of protecting crops at a locus from competition by grass weeds which comprises applying to the locus a 2-alkyl glycerol derivative or composition of the invention.

The compounds of the invention may be used in admixture with other herbicides and pesticides. In particular, the may be mixed with active materials possessing pre-emerge ce activity against-broad-leaf weeds.-to give herbicide combinations exhibiting broad-spectrum pre-emergence ac-tivity. Examples of such active materials are s-triazine derivatives, such as 2,4-bis-(isopropylamino) -6-methylthio-s_-triazine, or 2-chloro- -ethylamino-6-isopr.opylamino- -triazine, pyridazole derivatives, such as 5-amino-4-chloro-2-phenylpyridaz-3-one, or 1,4-naphthaquinone derivatives.

The invention is further illustrated in the following Examples .· · · ■ - ■ . .. .

EXAMPLE I - ^-Benzyloxymethyi-^^^-trimetnyl-l^-djxoiane (a) Preparation of 2-methyiglyceroi Methallyl alcohol (20.0 g), alumina (20.0 g) and tungstic acid (2.0"g) in water (100 ml) were heated to 60°C"and then hydrogen peroxide (31.6 ml of 30 w/v solution) was slowly added.

During the addition the temperature of the mixture was maintained at 60°C by cooling. When the addition was complete the mixture was maintained at 60°C for a further hour and then at 95°C for 2 hours. After cooling the mixture was filtered and the filtrate passed through two columns containing respectively Amberlite - IRA 400 and Permutit Zeo-Carb. 225. The solvent was then removed from the solution to give the crude 2-methylglycerol which was not purified further. - (b) Preparation, pf3-hydrQxymethyI-2,2, -triniethyl- 1,3-dioxoiane 2-Methylglycerol (5.0. g, prepared as in (a)) acetone (150 ml) , " -toluene sulphonic acid (1.5 g) and petroleum ether (150 ml, b.p. 40-60°C) were heated together for 24 hours at reflux temperature under two Vigreux columns (40 cm length each) and a Dean-and-Stark trap for removal of water. The reaction. mixture was cooled and fused sodium acetate ( 1.5 g) was added. The suspension was stirred at room temperature for 30 minutes and then filtered. The solvents were removed from the filtrate under reduced pressure and the residue was fractionally distilled. 4-Hydroxymethyl-2, 2,4-trimethyl-l, 3~ dibxolane was obtained as a colourless liquid having a b.p. 77°C at 12 mm Hg.

Preparation of 4-benzylpxymethyl-2, 2, 4-trimethyl- i, 3-dioxolane 4-Hydroxymethyl-2, 2,4-trimethyl-l, 3-dioxolane ( 10 g, prepared as in (b)) was added dropwise to et'.gtirred suspension of sodium hydride ( 3 g, 0$ dispersion in oil) in dry toluene ( 150 ml). When the addition was complete the solution was heated under reflux until no more hydrogen was evolved. Benzyl chloride ( 7 · 85 g) was added to the refluxlng solution over a period of 15 minutes, after which the solution was heated ! under reflux for a further 3 hours. The solution was then cooled, washed with water ( 3 x 30 ml), dried and the solvent removed under- reduced pressure. The residual oil was fractionally distilled to give the desired product as a colourless liquid having a b.p. 80°C at 0.2 mm Hg.

Analysis Calculated for C^HgQO^ s C 71.3 J H 8 ; 5# Found ί C 71.3; H 8.7# 4-Benzyloxymethyl-2, 2-dimethyl-4-n-propyl- Preparation of 2-n-propyl glycerol Formaldehyde (50 ml of 37-4l#w solution) and dimethylamine hydrochloride (53 g) were mixed to give a clear solution, to which was added slowly valeraldehyde (50 g) · The solution was maintained at 55°C for 1 hour and -then at 70°C for 22-24 hours. The crude product was separated by steam distillation, dissolved in methanol (100 ml) and reduced with Sodium borohydride (5· 25 g) in aqueous methanol (45 ml) at 30-40°C» When the reduction -was complete aqueous sodium hydroxide (120 ml of 13$ "solution) was added and the mixture heated at 80°C for 1 hour. The solution was; cooled and extracted with ether. The dried extracts were evaporated and the residual oil was dried with magnesium sulphate and fractionally distilled to yield 2-methylene-pentan-l-ol having a b.p. 6l-63°C at 15 mm Hg.

Following a series of reactions similar to those of Example 1 (a) - (c), but using 2-methylene~ pentan-l-ol as starting material the desired product was obtained as. a colourless liquid having a b.p. 97°C at 0.j5 mm Hg.

Analysis Calculated for C^H^O^ s C 72.7i H 9.1$ Found s ■ C 72.4; H 9-2$ Following procedures similar to those of Examples 1 and 2 further compounds were prepared, whose physical characteristics and analyses are given in Table 1.

TABLE 1 Boiling Compound point u/mm ng 4-benzyloxymethyl-4-n-hexyl-2, 2- Calcul dimethyl-l,3-dioxolane 124/0.3 Found 4-(4' -chlorobenzyloxymethyl)- Calcul 2, 2,4-trimethyl-l,3=dioxolane 94/0.1 Found 4- ( 41 -methylbenzyloxymethyl) - Calcul 2, 2,4-trimethyl-l,3-dioxolane 91/0.3 Found 4- ( 3F -methylbenzyloxymethyl) - Calcul 2,2I4-trimethyl-l,3-d^colane 90/0.3 Found 4- ( 3194 ' -dichlorobenzyloxymethyl) - Calcul 2, 2I4-trimethyl-l,3-dioxolane 121/0.3 Found 4~benzyloxymethyl-4-ethyl=2, 2= Calcul dimethyl-l,3-dioxolane 96/0.3 Found 4-benzyloxymethyl~4~isopropyl- Calcul 2,2-dimethyl-lJ,3-dioxolane 99/0.4 Found 4~benzyloxymethyl=2=isobutyl~ Calcul 2P4-dimethyl~lI)3=dioxolane 103/0.3 Found TABLE 1 (cont'd) Boiling Compound point o/mm Jig -benzy 1oxymethyl- 2-ethy 1 - Calculate 2, 4-dimethyl-1 , 3-dioxolane 98/0.5 Pound 4=allyloxymethyl~2,2,4-tri- Calculate methy 1 - 1 , 3=dioxolane 70/12 Found - 4~benzyloxymethyi~2, =dimethyl- Calculate 2=phenyl~l,3-dioxolane 125/0.15 Found 4= ( 4 ' ~fluorobenzyloxymethyl) ~ Calculate 2,2,4~trimethyl~l,3=dioxolane 83/0.3 Found 4-benzyloxymethyl~2, 2~dip enyl~ m. p. Calculate 4=methyl=li,3=dioxolane 54=56°c Found - 4= (pyrid-4 ' =yl~methoxymethyl) = Calculate 2,2,4~trimethyl-l,3~dioxolane 97/0.4 Found Pound 4= ( bl phenyl= 1 =yl—rnethoxymethyl) - Calculate 2,2,4¾rimethyl~l,3-dioxolane 142/0.15 3 4= ( 2 ' , 1 , 6' -trichlorobenzyloxy- Calculate methyl) =2,2, -trimethyl-l,3-di- 132-138 Found oxolane /OA TABLE 1 (cont'd) Boiling Compound point - ( cyclohexylmethoxymethyl)- 88-89 Calculat , 2, -trimethyl-l, 3-dioxolane /l.O Found -benzyloxymethyl=4-methyl= Calculat -phenyl-lJ>3-dioxolane 136/0.15 Found EXAMPLE. A |- 3-Benzylpxymethyl- -methyl-2-p-tplyl-l,3- dioxolane 3-Benzyloxy-2-methylpropane-lJ)2-diol (6.5 g), £-tolualdehyde (4.0 g) and p_-toluenesulphonio aoid in benzene (200 ml) were heated together . under reflux until no more water was liberated.

The oooled solution was washed first with 5$ potassium carbonate solution and then water.

The solution was then dried and the solvent removed, under reduced pressure. The residual liquid was purified by chromatography on alumina using benzene as eluant to yield the desired produot (η 1.5361).

Analysis Calculated for C^H^O^ s C 76.5; H 7. # Found : C 76.6; H 7· Following a procedure similar to that given the previous Example, further compounds were prepared whose physical characteristics and analyses are set out in Table 2.

TABLE 2 Compound b.p. °C/mm Hg ' or njj 4-benzyloxymethyl-2- (4-methoxy- ng6 1.5422 Calculated for phenyl) - -methyl-l,3-dioxolane Found 4-benzyloxymethyl-2- (4-chloro- Calculated for phenyl) -4-methyl-l,3-dioxolane np6,¾.5482 Found 4-benzyloxymethyl-2- (4-nitro- Calculated for phenyl)- -methyl-l,3-dioxolane Found -benzyloxymethyl-2- (fur-2-yl) - Calculated for 4-methyl-l,3-dioxolane τξ6'5 1.5198 Found A=benzyloxyme.thyl-4-meihyl-2- Calculated for (pyrid-2-yl)l-,3-dioxolane " Found TABLE 2 (cont*d) 4-Benzyloxymethyl-2J4-dimethyl--lJ3-dloxolane 3-Benzyloxy-2-methylpropane-l,2-d.iol (5.0 g), 1,1-diethoxyethane (5.0 g) and p_-toluene- sulphonic acid were heated at 110-115°C with stirring until no more alcohol was evolved.

The mixture was then heated at 140-145°C for minutes. After cooling the mixture was dissolved in ether and the resulting solution was then washed with 5$ potassium carbonate solution followed by water. The solution was dried over anhydrous magnesium sulphate and the solvent was removed under reduced pressure to yield a liquid which on distillation gave the desired product having a b.p. 8l-82°C at 0.3 mm Hg.

Analysis Calculated for C 13Hl8°3 C 70.3; H 8.1# Found C 70.6; H 8.0# Following a procedure similar to that of Example 7 -the following compounds were also prepared "benzyipxymethyl-2-brom i^-dioxolane, b.p. 114 C at 0.15 mm Hg Analysis Calculated for C^H^O-^Br s c 51.9; H 5.6$ Found ί C 51.9; H 6.0$ 4-benzyloxymethyl-2 'benzyl-4-methyi-l,3° dioxolane, b.p. 1 ^C at 0.2 mm Hg Analysis Calculated for % c 76, 6j H ΊΑ% Found : C 77.0; H 7.4$ -benzyloxymethyi-2"ethoxy dioxolane, b.p. 10¾°C at 0.4 mm Hg Analysis ; Calculated for C^H^O^ % C 66.8'; H 7.9$ Found % C 66.5; H 8.4$ -j?henoxymethyl -2J2J °trlniethyl-lB -dioxolane 4-Chlcromethyl-2, 2, 4~trimethyl-l, 3-dioxolane (5.0 g) and sodium phenoxide (j5«7 * prepared from pheriol and sodium hydride) in dimethyl sulphoxide (90 ml) were heated together at l40°C for 4 hours. The reaction mixture was diluted with water and the aqueous -solution extracted with ether. The ether extracts were dried and the solvent was removed under reduced pressure to yield a liquid which, on distillation, gave .the desired product having a b.p. 8j5.5°C at 0.3 mm Hg.

Analysis Calculated for Ο-^Η^Ο^ s C 70.3J H 8.1$ Found .·' C 70.7; H 8.1$ Following a procedure similar to that of Example 9 the following compounds were also prepared s 4-methyi-4-phenoxymethyi°°2-phenyl°lJ,3°°dioxolane Analysis - Calculated for Ο-^Η^Ο^ s C 75.6; H 6.7$ Found s C 75.8j H 6,9$ 4-furfuryloxymethyl-2, ?, 4rtrimethyl-l,3- dioxolane « 73.5°C at 0.5 mm Hg Analysis Calculated for C^gH^O^ s C 63.7; H 8;0# Found § C 64.0; H 8.0$ 4-Benzoyioxymethyl-2, 2, -trimethyl-l, 3-dioxolane A solution of benzoyl chloride (14.0 g) in dry carbon tetrachloride (30 ml) was added to a stirred, cooled solution containing 2-hydroxy- methyl-2,2,4-trimethyl-l,3-dloxolaiB (14„ 6 g) and pyridine (7»9 g) in carbon tetrachloride and thenheated under reflux for 1 hour. The - cooled solution was filtered and ether ( 200 ml) was added to tl&e filtrate. The ether solution was washed with 1% hydrochloric acid, saturated sodium bicarbonate solution land finally water, and then dried. The- solvent was removed under reduced pressure arid the residue was fractionally distilled. The fraction boiling at 106°C/0»4 mm Hg was cooled to -50°C and triturated with petroleum ether¾bo give the desired product having a m.p. 29-30°C.

Analysis Calculated for C^H^O^ Ϊ C 67.2j H 7. $ Found ; C 67. | H 7 » 3$ 4- (N-phenylcarbampylpxymethyl) -2, 2,4-trimethyl- 1,3-dioxolane ' ■ -Hydroxymethy 1 - 2 , 2, :-1rimethy 1 ÷ 1,3-dioxolane (14.6 g) , phenyl isocyanate ( 11.9 g) and tri- ethylamine (one drop) in methylene chloride ( 75 ml) : were heated 'together under reflux for 4 hours. The solvent and unchanged starting materials were removed- under reduced pressure. The residue was triturated with petroleum ether and ' then recrystalllzed from petroleum ether to give the desired product having a m.p. 59-60°C.

Analysis Calculated for C, ·,ΗΊ οΝ0·, ι C 63.3; H 7. 2; 14 19 4 N 5. # 5l .4^ 2, 4-Dichlorophenol ( 5» 43 g) was added to a stirred suspension of sodium hydride ( 0.8 g) in dry-dimethylsulphoxide ( 100 ml). When the reaction was complete 4-berizyloxymethyl-2- bromomethyl-4-methyl-l, 3-dioxolane ( 10.0 g, prepared as in Example 7) was added to the mixture which was then heated at 130°C for 1½ hours. The mixture -was then poured into water ( 1 1) and extracted with ether. The ethereal extracts were washed, dried and evaporated to leave a residue which on fractional distillation gave the desired product having a b.p. l8l°C at 0. 15 mm Hg.

Analysis Calculated for C1QHOA0,.Cl C 59 » 6; H 5 ό 2| 19 20 2 . cl l8o55g Pound s c βθ. Οι H 5 ° 5j Cl 18. 1 To benzyloxymethyl=2-raethylpropane~l, 2-diol ( 10 g) at 100 C were added with stirring · sodium ethoxide ( 0.14 g) and diethylcarbonate ( 12. 1 g) „ The mixture was heated with stirring and the ethanol which was formed was distilled at 79-8 °C. When the temperature of the reaction mixture reached 130°C, the heating was stopped and ammonium chloride ( 0. 15 g) was added.

The remainder of the ethanol and excess diethyl carbonate was removed under reduced pres= sure. The residue was then extracted with diethyl ether and the extracts filtered and fractionally distilled in vacuo to give the desired product having. a b.p. 122=123°C at 0. 15 mm Hg.

Analysis Calculated for C^H^O^ s C 64.9 ,° H 6.3$ Pound % C 64.7 H 6. ^ 3.5165/2 -f ' EXAMPLE. 5-Benzyloxy-5-i,nethyl -2-phenyl-lJ 3-diox&ne 2-Methylglycerol ( 25.05 g) and benzaldehyde ( 26.0 g) were mixed at room temperature arid dry hydrogen chloride ( 100-200 ml) was blown through the mixture. Benzene ( 500 ml) was added to the mixture and the water was removed azeotroplcally over a period of 18 hours, while a very slow stream of gaseous hydrogen ohloride was passed through the solution. The solvent was then removed under reduced pres- - sure and the crude product reorystallized from oyclohexane to give pure 5-hydroxy-5-methyl-2- phenyl-l, 3-dloxane.

The hydroxy compound so obtained was reaoted with benzyl chloride in a similar manner to that described in Example 1 (o) to give the desired product having a m.p. 56°C.

Analysis Calculated for C^gHggO. t C 76.1} H 7.0# Found s C 76. Oj H 7.1# EXAMPLE -t5 ]- Following procedures analogous to those used in the previous Examples for the preparation of the dioxolane dorivati on , furthar dioxane derivatives worn prepared, w owo phynloal oharaotorietios and ftvmlyuoo ar i.utb out in Table J. i TABLE 3 TABLE 3 (cont'd m.p. 0C Compound b.p. C/mm Hg or nD -benzyloxy-2-ethoxy-5-niethyl- Calc 1 ,3-dioxane b.p. 113/0.25 Pou =benzyloxy~5=methyl-2- ( 2=phenyl- Calc ethyl)-l, 3=dioxane (isomer 1) m.p. 3^-35 Pou ~benzyloxy-5=methyl-2- ( 2-phenyl- Calc ethyl) -1, 3-dioxane (isomer 2) m.p. 53-55 Fou To evaluate their herbicidal activity, the compounds of the invention were tested using as a representative range of plants s- ma'ize, Zea mays (Mz)j oat, Avena sativa (0) ; rye grass, Lolium perenne (RG)j pea, Pisum sativum (P)j linseed, Linum usitatissium (L) j mustard, Slnapis alba ( )j and sugar beet, Beta vulgaris (SB) . ■ - The tests fall into two categories, pre- emergence and post-emergence.. The pre-emergence tests involved spraying1 a liquid formulation of the compound onto the soil in which the seeds of the plant species mentioned above had recently been sown. The post-emergence tests involved two types of test, viz., soil drench and foliar spray tests. In the soil drench tests the soil in which seedling plants of the above species were growing, was drenched- with a liquid formulation containing a compound of the invention, and in the foliar spray tests the seedling plants were sprayed with such a formulation.

The soil used in the tests was a steam- sterilized, .modified John Innes Compost mixture in which half the peat, by loose bulk, had been replaced by vermiculite.

The formulations used in the tests were prepared by diluting with water and solutions of the compounds in acetone containing 0.4$ by weight of ah alkylphenol/ethylene oxide condensate available under the trade name Triton X-155. In the soil spray and foliar spray tests the acetone solutions were diluted with an equal volume of water and the resulting formulations applied at two dosage levels corresponding to 10 and 1 kg of active material per hectare, respectively, in a volume equivalent to 400 litres per hectare. In the soil drench tests one volume of the acetone solution was diluted to 155 volumes with water and the resulting formulation applied at one dosage level equivalent to kilograms of active material per hectare in an volume equivalent to approximately 5*000 litres per hectare.

In the pre-emergence tests untreated sown soil and in the post-emergence tests untreated so^il bearing seedling plants were used as controls.

The herbicidal effects of the compounds were assessed visually seven days after spraying the foliage and drenching the soil and eleven days after spraying the soil, and were recorded on a 0-9 scale. A rating 0 indicates no effect on the treated plants, a rating 2 indicates a reduction in fresh weight of stem and leaf of the plants of approximately 25 , a rating 5 indicates a reduction of approximately 55$, a rating 9 indicates a reduction of 95$* etc.

The results of the tests are set out in Table 4.

In the tests on certain of the compounds oat was replaced by rice, Oryza sativa (R) and rye grass 'was replaced by barnyard. :grass, Eonlnochioa crusgaiii (BG) . The results of these te6ts are given in Table 5.

TABLE 4 Compound Dosage Post-emerge kg/ha soil drench Mz · 0 RG P L M SB 4-benzyloxymethyl-2, 2,4- 10 5 5 5 27 03 trimethyl-l,3-dioxolane 1 4-( 1 -chlorobenzyloxy- 10 4 0 00000 methyl)-2,2,4-trimethyl-1,3-dipxplane 1 4=benzyloxymethyl-4-n- 10 8 6 6 05 0 0 propyl-2s =dimethyl-l,3-dioxolane 1 4-benzyloxymethyl-2-iso- 10 7 5 5 0 0 0 0 butyl-2,4-dimethyl-1,3-dipxolane 4=(4' -methylbenzyloxy- 10 2 0 O O 3 O O methyl) -2,2,4=trimethyl-1,3-dioxolane 1 4=(3' -methylbenzyloxy- 10 3 0 0 0 0 00 methyl) -2,2, -trimethyl-1,3-dioxolane 1 4- (3'A' -dichlorobenzyl- 10 0 0 0 0 0 0 0 oxymethyl)-2,2,4-trimethyl 1,3-dioxolane TABLE 4 (cont Dosage Compound kg/ha soil drench 4-benzyloxymethyl-4- 10 8 5 4 054 2 ethyl-2,2=dimethyl~l,3-dioxolane 1 -benzyloxy-5-methyl-2- 10 8 8 7 024 0 phenyl-l,3-dioxane 1 ¾-benzyloxymethyl=4- 10 7 7 7.04 20 methyl-2-phenyl-1,3-dioxolane 1 4~benzyloxymethyl~2= 10 7 : 5 5 04 1 0 eth l-2, -dimethyl-l,3-dioxolane 1 4-benzyloxymethy1-4- 10 0 0 0 0000 methyl-1,3-dioxolan-2-one 1 4-benzyloxymethyl~2,4- 10 5 2 5 00 00 dimethyl=2-phenyl-l,3-dioxolane 1 TABLE 5 TABLE 5 (cont'd) TABLE 5 (cont'd) TABL55 (cont'd) EXAMPLE - The fungicidal activity of the compounds of the invention was tested as follows s- Intact leaves or leaf pieces of vine, potato and wheat were supported on water-saturated seed germination pads in 9 cm petri dishes and were sprayed with aqueous suspensions containing 1000 ppm of the test compound. The leaves or leaf pieces were allowed to dry arid were then inoculated' with spores of-Piasmopara viticoia (vine downy mildew) , Phytophthora infestans (potato late blight) and Puccina recondita (brown wheat rust) , respectively. Observations on the development of disease symptoms were made after 2-7 days.

The results of the tests are shown in Table 6 in which a result 2 indicates more than 80# control of the fungal disease, a result 1 indicates 50-8o# control and a result 0 indicates less than 50$ control.

TABLE 6 Fungici Compound P.viticola P. .4-benzyloxymethyl-2,2,4-trimethyl-l,3-dioxolane 1 -benzyloxy-5-niethyl-2-phenyl-l,3-dioxane 1 -benzyloxymethy1- -methy1-2-pheny1-1,3-dioxolane 2 2-benzyloxymethyl-2-rnethyl-l f4-dioxaspiro > 2 .¾7denane 2-benzyloxymethyl-2-isethyl-l ,4-dioxaspiro 4. 7-ionane 0 3-benzyloxy-3-meth l-l,5-dioxaspiro .5/undecane 1 3-benzyloxy-3-methyl-1, 5-dioxaspiro 1 ^ .6/duodecane 35165/2

Claims (1)

1. CLAIMS 2-Alkyl glycerol derivatives of the general formula : wherein R represents an alkyl group of 1-6 carbon atoms; ^ and each individually represents a hydrogen atom, an alkyl group of 1-6 carbon atoms optionally substituted by a halogen atom or a phenyl group, an alkoxy group of 1-6 carbo atoms, a phenyl group optionally substituted by one or more halogen atoms or by an alkyl or alkoxy group of 1-6 carbon atoms or by a nitro group, or a. furyi- pyrid l or phenoxyalkyl group, optionally eubBtituted ' by one or more halogen atoms, : or and together represent a polymethylene group, or ^ and R2 together with the carbon atom to which they are bound represent a carbonyl group; and Y represents an alkenyl group of up to 6' carbon atoms or a phenyl group, a benzyl group optionally substituted in the benzene ring by one or more .halogen atoms or by a methyl or phenyl group, or a furfuryl or pyridylmethyl group, or a cyclohexylmethyl, benzoyl or N- phenylcarbamoyl group, 2 „ 4-Benzyloxymethyl-2 , 2-dimethyl-4-n-propyl-l, 3-dioxolane» 3. 4-Benzyloxymethyl-2 , 2-dimethyl-4-ethyl-l, 3-dioxolaneo 4o 5-Benzyloxy-5-methyl-2-phenyl-l, 3-dioxane· 35165/2 -38- 5. 2-Benzyloxymethyl-2-methyl-l,4-dioxaspiro 4.5,7 decane, 6. 3-Benzyloxy~3-methyl-l,5-dioxaspiro 5.5-7 undecanee 7. 2-Alkyl glycerol derivatives as claimed in claim 1, specifically named herein excluding those claimed in claims 2-£. 8. Process for preparing 2-alkyl glycerol derivatives as claimed in Claim 1, which comprises reacting the corresponding raono-hydroxy derivative with an organo halo derivative of formula: Hal-Y III . wherein Y represents an optionally substituted hydrocarbyl or acyl group, and Hal represents a halogen atom. 9o Process according to claim 8, in which the mono-hydroxy derivative is used in the form of a salt. 10. Process according to claim 9, in which tho Bait is an alkali metal salt. 11. Process according to claim 10, in which the salt is the sodium salt . 12. Process according to any one of the claims 8-11, in which Hal represents a chlorine atom. 13. Process according to any one of the claims 8-12, in which the reaction is carried out in an organic solvent. 14. Process according to claim 13, i which the organic solvent is toluene. 15. Process for preparing 2-alkyl glycerol derivatives as claimed in Claim 1, wherein the group Y represents a N- henyl. mono' Ε· oubo'tl'bu-bed carbamoyl group, which comprises reacting i 35165/2 '! -39- ■ phenyl j the corresponding mono-hydroxy derivative with an organic I isocyanatee i ; j 16, Process according to claim 15, in which the reactio is carried out in the presence of an organic base. 1 17o Process according to claim 16, in which the organic base is a tertiary amine. 18. Process according to claim 17, in which the tertiary amine is triethylamine . 19· Process according to any one of the claims 15-18, in which the reaction is carried out in an organic solvent 0 20. Process according to claim 19, in which the solvent is i methylene chloride. ■ 1 21. Process for preparing 2-alkyl glycerol derivatives as ! claimed in claim 1, which comprises reacting an appropriate halo propane derivative with a salt of formula :- MetO - Y IV wherein Met represents an alkali metal. 22. Process according to claim 21, in which the alkali metal is sodium« 23. Process according to claim 21 or 22 in which the reaction is carried out in a polar organic solven 0 24. Process according to claim 23, in which the solvent is dimethyl sulphoxide. . 25. Process according to any one of the Claims 21-24, \ ' in which Y in formula IV represents a phenyl or furfuryl group. ProooBS £ov proposing 2-alkyl glyoerol der-ivativeo -ao alaimad in Claim j, whloh oomprioeo hydr-oliolng the oorreopond- I ing 2-alkyl gl cerol nnmpminri . 35165/3 - 40 - 20; Process for preparing 2-alkyl glycerol derivatives as claimed in Claim 1, which comprises reacting the arrres-ponding dioj. wijijh a carbonyl compound of formula or an acetal or ketal derived from such a carbonyl compound, in the presence of an acid. 27. Process according to Claim 26, in which the acid is an inorganic acid or arylsulphonic acid. 28. Process according to Claim 27* in which the acid is hydrochloric acid or ^-toluenesulphonic acid. 29; Process according to any one of the Claims 26-28, in which the reaction is carried out in an aromatic hydrocarbon as solvent* ?0. Process according to Claim 29 in which the aromatic hydrooarbon is benzene or toluene. 31. Process for preparing 2-alkyl glycerol derivatives as claimed in Claim 1, wherein and Rg together with the carbon atom to which they are bound represents a carbonyl group, which comprises reacting the corresponding diol with a dialkyl carbonate in the presence of a base. 32. Process according to Claim 31, in which the dialkyl carbonate is dieth l carbonate. 33. Process according to Claim 31 or 32, in which the base is an alkali metal alkoxide. 34. Process according to Claim 33» in which the base is sodium ethoxlde. derivative as claimed in any one of the laims ' a composition as claimed in Claim 37.