Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
  • C07C69/66—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety
  • C07C69/73—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety of unsaturated acids
  • C07C69/738—Esters of keto-carboxylic acids or aldehydo-carboxylic acids
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/03—Preparation of carboxylic acid esters by reacting an ester group with a hydroxy group
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
  • C07D309/34—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members
  • C07D309/36—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members with oxygen atoms directly attached to ring carbon atoms
  • C07D309/38—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members with oxygen atoms directly attached to ring carbon atoms one oxygen atom in position 2 or 4, e.g. pyrones

Definitions

• the invention relates to a ner process for the preparation of 6,6,6-trihalo-3,5-dioxohexanoic esters of the formula
• substituents X are each independently fluorine, chlorine or bromine and 1 in which R is each alkyl, cycloalkyl, aryl or aralkyl, and R is alkyl, cycloalkyl, allyl or benzyl, starting from pyranones of the formula
• Ethyl 6,6,6-trihalo-3,5-dioxohexanoate of the formula I are used, for example, for the preparation of herbicides and agrochemicals (JP-A-06-049039).
• BEST ⁇ TIGU ⁇ GSKOPIE A ner process for the preparation of 6,6,6-trifluoro-3,5-dioxohexanoic acid tert-butyl ester from trifluoroacetic acid (2,2,2-trifluoroethyl) ester and acetoacetic acid tert-butyl ester is disclosed in OA-02/02547.
• Another alternative production variant for substituted tricarbonyl compounds proceeds via the ring opening of a pyranone, such as, for example, dehydroacetic acid, which is converted into methyl 3,5-dioxohexanoic acid using Mg (OMe) 2 in methanol (Batelaan, JG, Synthetic Commun. 1976, 6, 81- 83).
• a pyranone such as, for example, dehydroacetic acid
• the object of the present invention was therefore to provide a simple ner process for the preparation of 6,6,6-trihalo-3,5-dioxohexanoic acid alkyl esters and their enols and enol ethers, which can use easily accessible pyrones as starting compounds.
• the substituents X each independently represent fluorine, chlorine or bromine
• the present process is characterized in that no mass loss occurs when the ring is opened and the number of carbon atoms contained in the basic structure is retained.
• the starting compounds of formula II of the process according to the invention are easily accessible.
• 4-hydroxy-6-trifluoromethyl-pyran-2-one can be prepared by reacting trifluoroacetic acid with ketene.
• alkyl means in particular a linear or optionally branched group with 1 to 8 carbon atoms, optionally substituted with halogen, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl , Pentyl, hexyl, heptyl, octyl.
• halogen such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl , Pentyl, hexyl, heptyl, octyl.
• Cycloalkyl here and below means in particular a cyclic group with 3 to 8 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl.
• aryl means in particular an aromatic group with 6 or 8 carbon atoms, optionally substituted with alkyl and or halogen, such as phenyl, p-to ⁇ y ⁇ or naphthyl.
• aralkyl means in particular an alkyl group substituted by an aryl group, such as phenylethyl, where the alkyl group contains 1 to 4 carbon atoms, and the aryl group is an aromatic or heteroaromatic group optionally substituted by halogen, having 4 to 8 carbon atoms, such as for example phenyl, naphthyl, 2- or 3-furanyl, 2- or 3-thiophenyl or 2-, 3- or 4-pyridinyl.
• aryl group such as phenylethyl
• the alkyl group contains 1 to 4 carbon atoms
• the aryl group is an aromatic or heteroaromatic group optionally substituted by halogen, having 4 to 8 carbon atoms, such as for example phenyl, naphthyl, 2- or 3-furanyl, 2- or 3-thiophenyl or 2-, 3- or 4-pyridinyl.
• substituents X are each independently fluorine, chlorine or bromine and in which R 1 is each alkyl, cycloalkyl, aryl or aralkyl, and R 2 is alkyl, cycloalkyl, allyl or benzyl, compounds of the formula
• Suitable reagents for the preparation of compounds of the formula III according to the invention are, for example, dimethyl sulfate, diethyl sulfate, methyl iodide, ethyl bromide, methyl tosylate, ethyl tosylate, phenyl tosylate, allyl chloride, allyl bromide, benzyl chloride or benzyl bromide.
• O ⁇ ⁇ M n + means M n + preferably Li + , Na + , K + ,
• strong acids are understood to mean, for example, HCl, HBr, HI, H 2 SO, trifluoroacetic acid or solid acids such as, for example, acidic zeolites such as H-ZSM-5 or acidic sheet silicates.
• Weak acids in the process according to the invention are understood to mean, for example, acetic acid and aqueous dilute acids of HCl, H3PO 4 or H 3 SO 4 or the addition of strong acids after adding water beforehand.
• compounds of the formula III are converted into compounds of the formula I in which X is fluorine and R 1 -s-alkyl, the radical R 2 being split off.
• R 1 is C 1-4 alkyl.
• R 1 is methyl.
• Z isomers is influenced by various influences such as, for example, the solvent, the temperature or, if appropriate, by protonating or deprotonating additives.
• the solvent the temperature or, if appropriate, by protonating or deprotonating additives.
• the enols of compounds of the formula I differ from one another by the enolized carbonyl group and the position and orientation of the resulting double bond (s).
• the carbonyl groups at C 3 and / or C 5 can be enolized.
• the enols are usually in the form of mixtures of several forms.
• the invention also includes compounds of the formula
• X each independently represents F, Cl or Br and wherein R 2 is alkyl, cycloalkyl, allyl or benzyl.
• E and Z isomers in which X each independently denotes F, Cl or Br, and in which R 1 is alkyl, cycloalkyl, aryl or aralkyl, and in which R 2 is alkyl, cycloalkyl, allyl or benzyl.
• the compounds of the formula Ib can be present as E and / or Z isomers. Depending on the external conditions, only the carbonyl group at C 5 can be enolized. The number and position of the resulting double bonds at C 2 / C 3 and / or C 4 / C 5 correspond to the E and Z isomers of the oleols of the compounds of the formula I.
• 3,3,3-Trihalo-3,5-dioxohexanoic acid alkyl esters can be prepared from 4-methoxy-6-trihalomethyl-pyran-2-ones by the process described above.
• 6,6,6-trifluoro-3,5-dioxohexanoic acid methyl ester is prepared from 4-methoxy-6-trifluoromethyl-pyran-2-one.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Pyrane Compounds (AREA)

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• 2004
  • 2004-10-22 EP EP04817266A patent/EP1680391A1/de not_active Withdrawn
  • 2004-10-22 CN CNA2004800314361A patent/CN1871202A/zh active Pending
  • 2004-10-22 CN CN200910175012A patent/CN101693664A/zh active Pending
  • 2004-10-22 US US10/577,070 patent/US7351851B2/en not_active Expired - Fee Related
  • 2004-10-22 CN CN2010105359224A patent/CN102030645A/zh active Pending
  • 2004-10-22 CA CA002541843A patent/CA2541843A1/en not_active Abandoned
  • 2004-10-22 WO PCT/EP2004/011970 patent/WO2005040087A1/de active Application Filing
  • 2004-10-22 JP JP2006536059A patent/JP4638441B2/ja not_active Expired - Fee Related
• 2006
  • 2006-05-03 US US11/416,212 patent/US7348450B2/en not_active Expired - Fee Related
• 2008
  • 2008-02-28 US US12/071,991 patent/US7781601B2/en not_active Expired - Fee Related

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