GB2055819A - Cyclobutane compounds - Google Patents
Cyclobutane compounds Download PDFInfo
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- GB2055819A GB2055819A GB8023428A GB8023428A GB2055819A GB 2055819 A GB2055819 A GB 2055819A GB 8023428 A GB8023428 A GB 8023428A GB 8023428 A GB8023428 A GB 8023428A GB 2055819 A GB2055819 A GB 2055819A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
- C07C49/88—Ketenes; Dimeric ketenes
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
- C07C45/65—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by splitting-off hydrogen atoms or functional groups; by hydrogenolysis of functional groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
- C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
- C07C45/76—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton with the aid of ketenes
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/87—Preparation of ketenes or dimeric ketenes
- C07C45/89—Preparation of ketenes or dimeric ketenes from carboxylic acids, their anhydrides, esters or halides
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
- C07C49/385—Saturated compounds containing a keto group being part of a ring
- C07C49/457—Saturated compounds containing a keto group being part of a ring containing halogen
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
- C07C49/587—Unsaturated compounds containing a keto groups being part of a ring
- C07C49/593—Unsaturated compounds containing a keto groups being part of a ring of a three- or four-membered ring
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Novel cyclobutane compounds contain a <IMAGE> group, where Y is F, Cl or Br, Q is -(CF2)mW where W is H, F or Cl and m is 1 or 2 and 2 is Y or Q. The compounds are intermediates for the preparation of synthetic pyrethroids.
Description
SPECIFICATION
Cyclobutane compounds
This invention relates to cyclobutane compounds which are useful as intermediates in the synthesis of pyrethroids.
According to the present invention there are provided cyclobutane compounds having the general formula:
wherein R1 represents a group of the formula
Y Y
-CH2-C-Q or -CH = CQ z in which Y represents a fluorine, chlorine or bromine atom,
Q represents the group -W(CF2)m in which W is hydrogen, fluorine or chlorine and m is 1 or 2 and Z is Y or
Q,
R2 represents hydrogen or halogen,
R3 represents hydrogen or lower alkyl,
R4 represents lower alkyl, and
(i) X1 and X2, and X3 and X4, together with the carbon atoms to which they are attached, represent carbonyl groups, or
(ii) X7 and X2 together with the carbon atom to which they are attached represent a carbonyl group and
X3 and X4, which may be the same or different, represent hydrogen or alkyl, cycloalkyl, aralkyl, alkaryl or aryl groups which may themselves be further substituted and which may contain hetero atoms, or hydroxyl, alkoxy, aryloxy, halogen, alkylsulphonyloxy, arylsulphonyloxy, cyano, formyl, carboxylic acid, carboxylic acid halide, carboxylic acid ester, aminocarbonyl, (N-substituted)aminocarbonyl, (N,N-disubstituted)aminocarbonyl, alkylcarbonyloxy or arylcarbonyloxy group, or
(iii) X3 and X4 together with the carbon atom to which they are attached represent a carbonyl group and
X1 and X2 have the meanings defined for X3 and X4 in (ii), or
(iv) X', X2, X3 and X4 are each independently selected from the meanings defined for X3 and X4 in (ii) providing that at least one of X1, X2, X3, X4 is either hydroxyl, alkylsulphonyloxy, arylsulphonyloxy, alkylcarbonyloxy, arylcarbonyloxy or a similar 'masked' hydroxyl group, and
(v) ketals of compounds defined in (i), (ii) and (iii).
Throughout this specification the term "lower alkyl" means an alkyl group containing from 1 to 4 carbon atoms.
Particularly useful compounds of formula (I) are those in which R1 is the group CF3CC13CH7-, R7 iS hydrogen, R3 and R4 are both methyl, X and X2 together with the carbon atom to which they are attached represent a carbonyl group and X3 and X4 are both halogen, especially chlorine, or one of X3 and X4 is halogen and the other is hydrogen.
Such compounds may be obtained, for example, by reaction of a compound of the formula:
with monochloroketene or dichloroketene, which are conveniently generated in situ by reaction of dich loroacetyl chloride or trichloroacetyl chloride respectively with activated zinc.
For example:
The reaction between (II) and the mono- or dichloroketene is carried out in a solvent which may be, for example, diethyl ether or an excess of the acid chloride employed in generating the ketene. The use of acid chloride as solvent enables higher reaction temperatures to be achieved.
The monochlorocyclobutanone (IV) obtained according to the above process is obtained as predominantly one isomer, which on spectroscopic evidence is believed to be cis.
The compound of formula (II) may be obtained, for example, by continuously distilling a mixture of 5-methyl-2,2,4-trichloro-1,1,1-trifluorohexane, dimethylformamide and lithium bromide, collecting the distillate comprising dimethylformamide, 5-methyl-2,2,4-trichloro-l ,1 ,l-trifluorohexane, 2,2-dichioro-5 methyl-i 1,1 -trifluorohex-4-ene and hydrohalide salts of dimethylamine, precipitating the chlorofluorocar bons from the distillate by addition of water and isolating the 2,2-dichloro-5-methyl-1 1,1 ,1-trifluorohex-4-ene (11) from the chlorofluorocarbon mixture by distillation.The first distillation step of this process, which is the subject of a copending patent application, is preferably carried out under sub-atmospheric pressure in order to minimise by-product formation, and it is convenient to use from 20 to 8 mols of dimethylformamide and from 1 to 5 mols of lithium broniide per mol of trichlorotrifluorohexane starting material. The quantity of water which is used to precipitate the chiorofluorocarbons from the distillate is conveniently one half the volume ofthe distillate.
The cyclobutanone compounds (Ill) and (IV) may readily be converted into cyclopropane derivatives which are precursors of pyrethroid insecticides, as in the following scheme:
3 12 2 3 (i) NaOH CF3CCl2CH9 CH3 (Ill) Zn H H acetic ad Ev 3 > HCH3 HOH 2 (IVA) (V) HCl/ ethanol 3 \ Na co cyH;;cH% 4 DMF CF3CClHyCH33 G1 HLtr 5 -CRJ 2f H c%%H5 H c%c2H5 (VII) (VI) Compounds of formula (VII) are readily converted into the corresponding m-phenoxybenzyl, a-cyano-mphenoxybenzyl or a-ethynyl-m-phenoxybenzyl ester of the cyclopropane carboxylic acid. These latter esters are powerful insecticides as disclosed in, for example, German Offenlegungsschrift 2802962.
It is desirable, having regard to their subsequent conversion into cyclopropane derivatives, that the cyclobutane compounds of formula (I) should be 2-halocyclobutanones. Where these are not obtained directly in the initial cyclobutanone synthesis they may be obtained, for example:
(i) by halogenation of a suitable unhalogenated cyclobutanone [see, for example, R.B. Mitra and A.S.
Khana, Synth. Comm. 7, 245(1977)] (ii) by rearrangement of a halocyclobutanone where the halogen is not in the desired position with respect to the cyclopropane it is ultimately desired to produce (German Offenlegungsschrift 2813337)
(iii) by synthesis of a polyhalogenocyclobutanone and removal of the unwanted halogens by treatment with, for example, zinc and acetic acid or tributyl tin hydride [D.A. Bak and W.T. Brady, J. Org. Chem., 44, 107(1979) and Example 2 of this specification].
Various methods for the conversion of cyclobutanones or their derivatives into cyclopropane carboxylic acids or their derivatives are known. A selection of these methods, with references, is given below:
X (X = halogen, lz-tolt ne- > 02H (Ref. 1) { I, X sulphonyloxy, ethyl sulphonyloxy, pbromo benzenesulphonyloxy) rOR y > FCEO (Ref.1) > OCOR I -co (Ref.2) OR CO2R A R)C > CO2R + R (Ref.3)
References
1. J.M. Conia & J. Salaun, Acc. Chem. Res., 33 (1972)
2. German Offenlegungsschrift 2715931
3. J.P. Barnier, J.M. Denis, J. Salaun & J.M.Conia, Tetrahedron, 30, (1975) 4. J.M. Conia & J.M. Denis, Tetrahedron Letters, (1971) 5. European Patent Application No. 1089
6. P.D. Klemmensen, H.K.Andersen, H.B. Madsen & .Svendsen,J Org. Chern.,44,416(19791 It will be appreciated by those skilled in the art that in applying syntheses such as those outlined above, due regard must be given to the disposition ofsubstituents with respect to the substitution pattern desired in the final cyclopropane. Also, additional transformations may be necessary, for example, -CHOo -CO2R.
The reaction between the compound of formula (II) and mono- or dichloroketene may be extended to the analogous reaction with the compound of formula:
whereby cyclobutanones having the group F3C - CCI = CH - in place of F3CCC12CH2- are obtained.
The invention is illustrated by the following Examples in which percentages are by weight.
EXAMPLE 1 Synthesis of 2,2-dichloro-4(2', 2'-dichloro-3 ,3', :3:3'-trifluoroprop ylj-3,3-dimefhylcyclobutanone 6111)
(a) Activation of zinc
Zinc dust (60g) was washed under nitrogen for 1 minute with 3% hydrochloric acid (40 ml), filtered, washed with further 3% hydrochloric acid (3 x 40 ml) then with oxygen-free water (4 x 40ml) and finally with oxygen-free acetone (4 x 40 ml), and dried under nitrogen. The zinc dust was added to a solution of hydrated copper sulphate (5g) in oxygen-free water (100 ml) and stirred for 1 hour, filtered, washed as before with water and acetone, and dried under vacuum.
(b) Preparation of the dichlorocyclobutanone
To a 250cc. round bottom flask fitted with condenser, stirrer, and dropping funnel were charged, under nitrogen, activated zinc (5g), 2,2-dichloro-5-methyl-1,1,1-trifluorohex-4-ene (1 1.5g) and anhydrous ether (100 ml). To this stirred mixture was added during 10 minutes a solution of freshly distilled trichloroacetylchloride (30 g) and freshly distilled phosphorous oxychloride (8.379) in further anhydrous ether (40 ml). The resulting mixture was heated at reflux and monitored by g.l.c. for cyclobutanone formation. After approximately 3 hours the mixture was filtered and most of the solvent was removed under reduced pressure.Hexane (400 ml) was added and the resulting precipitate was discarded; the supernatent solution was evaporated to dryness and the residue was crystallised from cold ether to afford the dichlorocyclobutanone (III) Yield 10.7 g = 62%; m.p. 63-64 C; found: 33.0%C; 2.4%H; 43.4%Cl; C9H9Cl4F3O requires: 32.6%C; 2.7%H; 42.7%Cl.
Infrared: 1810cm- (strong, C=O); Hnmr (CDCl3) 81.2 (s, 3H), 1.6 (s, 3H), 2.25-2.85 (split q, 2H), 3.9-4.15 (broad t, H). Mass spectrum m/e 295 (M±Cl), 124 ( C(CH3)2-CCl2); accurate mass measurement confirmed this latter ion as C4H6Cl2 (Oppm error) and thus the orientation of addition of ketene to olefin to be that giving structure (III).
EXAMPLE 2 Dechlorination of (Ill) to give 2-chloro-4K2' 2'-dichloro-3',3', 3'-trifluoropropyl)-3,3-dimethylcyclobutanone {I VAJ
(III) Zn/acetic acid > CE 2 /CH3 CE - C - C" I I C -- CEI Cl o (IVA) The dichlorocyclobutanone (lil) from Example 1 (1.0 g) was dissolved in a mixture of acetic acid (15 ml) and dry ether (10 ml), stirred under nitrogen and maintained at 3-5=C. Zinc dust was added in small portions and the course of the dechlorination was constantly monitored by glc. (5 ft, 10% E301 on acid washed celite at 138 C).When all the starting material (III) had been consumed the excess zinc was immediately removed by filtration and the filtrate was evaporated under reduced pressure. The residue was dissolved in dichloromethane, washed with water, dried (Na2SO4) and evaporated to afford a mixture of cis and trans 2-chloro-4-(2',2'-dichloro-3',3',3'-trif luoropropyl)-3,3-dimethyl cyclobutanone (95%); infrared 1795cm-1 (strong, C=O).
EXAMPLE 3
Conversion of (IVA) into
A mixture of cis and trans 2-chloro-4-(2',2'-dichloro-3',3',3'-trifluoropropyl)-3,3-dimethylcyclobutanone (IVA) as prepared in Example 2 (2.0 g) was stirred at 60 C with 1.0 N aqueous sodium hydroxide solution (50 ml) until a clear solution was obtained. This solution was cooled to room temperature and acidified with concentrated hydrochloric acid. The precipitated acid was extracted into dichloromethane, washed with water, dried (Na2SO4) and evaporated to yield 3-(2',2'-dichloro-3',3',3'-trifluoropropyl)-2,2- dimethylcyclopropane-1-carboxylic acid (V) (90%). Esterification of the free acid with ethanolic hydrogen chloride afforded the ethyl ester (Vl) (82%), which was'heated with sodium carbonate in dimethylacetamide (4.5 hours at 1600C), cooled, diluted with dichloromethane and filtered.The filtrate was evaporated and then purified by short path distillation to afford ethyl 3-(2'-chloro-3',3',3'-trifluoroprop-1-enyl)-2,2- dimethylcyclopropane-1-carboxylate (VII) (65%) (30 : 70 cis-trans).
EXAMPLE 4
Direct synthesis of cis-2-chloro-4-(2:2 ,2'-dichloro-3',3',3' -trifluoropropyl)-3,3-dimethylcyclobutanone
Activated zinc (50g) prepared as in Example 1 was added to 2,2-dichloro-5-methyl-1,1,1-trifluorohex-4-ene (57.4g) and the mixture was stirred under nitrogen. To this mixture was added freshly distilled dichloroacetyl chloride (2509) containing freshly distilled phosphorous oxychloride (479). The entire reaction mixture was then maintained at reflux under nitrogen for several days before cooling, filtering and stripping under reduced pressure. The residue was extracted with hexane and the hexane extract washed with saturated brine, with aqueous sodium bicarbonate solution, again with brine, dried (Na2SO4) and evaporated. The crude product was distilled under high vacuum and then crystallised from cold ether to obtain the cis-monochlorocyclobutanone (IV): m.pt. 50-51 C; found: 36.3%C; 3.5%H; 35.6%Cl; 19.8%F; CgH10CI3F3O requires: 36.4%C; 3.4%H; 35.8%Cl; 19.2%F; Infrared: 1795cm- (strong, C=O); Hnmr (CDCl3) 61.03 (s, 3H), 1.6 (s, 3H), 2.2 - 2.85 (split q, 2H), 3.4 - 3.6 (broad, H), 4.8 (d, H). Comparison of nmr spectra, and glc analysis, shows this product to be the minor isomer produced in Example 2, and, since (IVA) is derived from structure (III), confirms that the structure must be as shown in (IV) above.
Claims (11)
1. Cyclobutane compounds having the general formula:
wherein R1 represents a group oftheformula
in which Y represents a fluorine, chlorine or bromine atom,
Q represents the group -W(CF2)m in which W is hydrogen, fluorine or chlorine and m is 1 or 2 andZisYorQ, R2 represents hydrogen or halogen, R3 represents hydrogen or lower alkyl,
R4 represents lower alkyl, and
(i) Xa and X2, and X3 and X4, together with the carbon atoms'to which they are attached, represent carbonyl groups, or
(ii) X1 and X2 together with the carbon atom to which they are attached represent a carbonyl group and
X3 and X4, which may be the same or different, represent hydrogen or alkyl, cycloalkyl, aralkyl, alkaryl or aryl groups which may themselves be further substituted and which may contain hetero atoms, or hydroxyl, alkoxy, aryloxy, halogen, alkylsulphonyloxy arylsulphonyloxy, cyano, formyl, carboxylic acid, carboxylic acid halide, carboxylic acid ester, aminocarbonyl, (N-substituted)aminocarbonyl), (N,Ndisubstituted)aminocarbonyl, alkylcarbonyloxy or arylcarbonyloxy group, or
(iii) X3 and X4 together with the carbon atom to which they are attached represent a carbonyl group and Xa and X2 have the meanings defined for X3 and X4 in (ii), or
(iv) X1, X2, X3 and X4 are each independently selected from the meanings defined for X3 and X4 in (ii) providing that at least one of X1, X2, X3, X4 is either hydroxyl, alkylsulphonyloxy, arylsulphonyloxy, alkylcarbonyloxy, arylcarbonyloxy or a similar 'masked' hydroxyl group, and
(v) ketals of compounds defined in (i), (ii) and (iii).
2. Cyclobutane compounds as claimed in claim 1 wherein R1 is the group CF3CC12CH2-, R2 is hydrogen, R3 and R4 are both methyl, X1 and X2 together with the carbon atom to which they are attached represent a carbonyl group and X3 and X4 are both halogen, or one of X3 and X4 is halogen and the other is hydrogen.
3. Cyclobutane compounds as claimed in claim 3 wherein the halogen represented by one or both X3 and X4 is chlorine.
4. Cyclobutane compounds as claimed in any one of claims 1 to 3 which are 2-halocyclobutanones.
5; Cyclobutane compounds as claimed in claim 1, substantially as hereinbefore described in any one of the foregoing Examples 1,2 or 4.
6. A process for the preparation of the cyclobutane compounds claimed in claim 1 which comprises reacting the compound of formula:
with monochloroketene or dichloroketene.
7. A process as claimed in claim 6 wherein the monochloroketene or dichloroketene is generated in situ by reaction of dichloroacetyl chloride or trichloroacetyl chloride with activated zinc.
8. A process as claimed in claim 7 wherein the reaction is carried out in a solvent.
9. A process as claimed in claim 8 wherein the solvent is an excess of the acid chloride employed in generating the ketone.
10. A process as claimed in claim 7, substantially as hereinbefore described in any one of the foregoing
Examples 1,2 and 4.
11. Cyclobutane compounds whenever obtained by a process as claimed in any one of claims 6 to 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8023428A GB2055819B (en) | 1979-08-07 | 1980-07-17 | Cyclobutane compounds |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB7927408 | 1979-08-07 | ||
| GB8023428A GB2055819B (en) | 1979-08-07 | 1980-07-17 | Cyclobutane compounds |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2055819A true GB2055819A (en) | 1981-03-11 |
| GB2055819B GB2055819B (en) | 1984-01-18 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8023428A Expired GB2055819B (en) | 1979-08-07 | 1980-07-17 | Cyclobutane compounds |
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| Country | Link |
|---|---|
| GB (1) | GB2055819B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2471360A1 (en) * | 1979-12-07 | 1981-06-19 | Ciba Geigy Ag | HALOGENOCYCLOBUTANONES, PROCESS FOR THEIR PREPARATION AND INTERMEDIATE PRODUCTS OF THEIR PREPARATION |
| EP0050777A2 (en) * | 1980-10-23 | 1982-05-05 | Bayer Ag | Preparation of cyclopropane-carboxylic-acid-substituted chloro-fluoro-alkyl esters, their derivatives and intermediates |
-
1980
- 1980-07-17 GB GB8023428A patent/GB2055819B/en not_active Expired
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2471360A1 (en) * | 1979-12-07 | 1981-06-19 | Ciba Geigy Ag | HALOGENOCYCLOBUTANONES, PROCESS FOR THEIR PREPARATION AND INTERMEDIATE PRODUCTS OF THEIR PREPARATION |
| EP0050777A2 (en) * | 1980-10-23 | 1982-05-05 | Bayer Ag | Preparation of cyclopropane-carboxylic-acid-substituted chloro-fluoro-alkyl esters, their derivatives and intermediates |
| EP0050777A3 (en) * | 1980-10-23 | 1982-08-18 | Bayer Ag | Preparation of cyclopropane-carboxylic-acid-substituted chloro-fluoro-alkyl esters, their derivatives and intermediates |
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| Publication number | Publication date |
|---|---|
| GB2055819B (en) | 1984-01-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| PE20 | Patent expired after termination of 20 years |
Effective date: 20000716 |