Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D273/00—Heterocyclic compounds containing rings having nitrogen and oxygen atoms as the only ring hetero atoms, not provided for by groups C07D261/00 - C07D271/00
  • C07D273/02—Heterocyclic compounds containing rings having nitrogen and oxygen atoms as the only ring hetero atoms, not provided for by groups C07D261/00 - C07D271/00 having two nitrogen atoms and only one oxygen atom
  • C07D273/04—Six-membered rings

Definitions

• This invention relates to processes for preparing intermediates, particularly of dicarboxylate oxadiazines of Formula I and hydrazine carboxylates of Formula II, which are useful in the preparation of arthropodicidal oxadiazines.
• WO95/29171 discloses the preparation of arthropocidal oxadiazines from dicarboxylate oxadiazines of Formula I and hydrazine carboxylates of Formula II.
• compounds of Formula I are prepared by reacting compounds of Formula II with a di(C 1 -C 3 alkoxy)methane in the presence of a Lewis acid, optionally in an inert solvent.
• the Lewis acids named are P 2 O 5 , BF 3 , SO 3 (0.9 to 4.0 molar equivalent required) and metal trifluoromethanesulfonates (0.1 to 0.5 molar equivalent required). All of the specifically named solvents for this transformation are halogenated (dichloromethane, 1,2-dichloroethane, chlorobenzene, a,a,a -trifluorotoluene).
• the process of the present invention allows for the use of a protic acid such as para-toluene sulfonic acid in catalytic quantities, such as 0.1 molar equivalent in a non-halogenated solvent (e.g. toluene) to provide good product quality in high chemical yield.
• a protic acid such as para-toluene sulfonic acid in catalytic quantities, such as 0.1 molar equivalent in a non-halogenated solvent (e.g. toluene) to provide good product quality in high chemical yield.
• the present invention pertains to processes for preparing oxadiazine dicarboxylates of Formula I which are racemic or enantiomerically enriched at chiral center*
• R 1 is F, Cl, or C 1 -C 3 fluoroalkoxy
• R 2 is C 1 -C 3 alkyl
• R 3 is a protecting group such as CO 2 CH 2 (C 6 H 5 ) comprising: reacting a compound of Formula II, which is racemic or enantiomerically enriched at*,
• This invention further pertains to processes for preparing compounds of Formula I as defined above comprising:
• step (b) reacting the compound of Formula II with a di(C 1 -C 3 alkoxy)methane in the presence of the same protic acid catalyst and inert solvent as used in step (a) under conditions which allow for the prompt removal of the by-product alcohol by distillation.
• C 1 -C 3 fluoroalkoxy refers to methoxy, ethoxy, n-propoxy and iso-propoxy which may be partially or fully substituted with fluorine atoms.
• fluoroalkoxy include CF 3 O and CF 3 CH 2 O:
• the compounds of Formula I can be prepared by the process of this invention which comprises the process variations as described below.
• Preferred compounds of Formula I are those where R 1 is F, Cl, CF 3 O or CF 3 CH 2 O, (more preferably Cl) and R 2 is CH 3 .
• protic acid can be used in the process of this invention as a catalyst.
• Suitable protic acid catalysts include mineral acids such as sulfuric acid and sulfonic acids such as aromatic, aliphatic and polymeric sulfonic acids.
• protic acids which do not co-distill to any significant extent with the by-product alcohol and which do not react with the dialkoxymethane to form products which could co-distill with the by-product alcohol.
• the preferred acids are those which catalyze both the reaction of compounds of Formula III with compounds of Formula IV, to give compounds of Formula II, and the conversion of compounds of Formula II to compounds of Formula I.
• Examples of the preferred acids are para-toluenesulfonic acid, mixtures of the isomeric toluenesulfonic acids, benzenesulfonic acid, naphthalene sulfonic acids, xylenesulfonic acids, methanesulfonic acid, sulfuric acid, and camphor sulfonic acids. Most preferred are para-toluenesufonic acid and mixtures of isomeric toluenesulfonic acids.
• protic acid While stoichiometric or greater amounts of the protic acid can be employed, it is preferred for reasons of greater commercial utility and/or ease of practice in the process for preparing compounds of Formula I, from either compounds of Formula II or compounds of Formula III that a catalytic amount of the protic acid be employed. It is more preferred that a total of between 0.01 and 0.20 molar equivalent of protic acid, relative to the compound of Formula II or Formula III, be employed. Most preferred is the process in which between 0.05 to 0.10 molar equivalent of protic acid is employed. In general, the use of 0.05 to 0.10 molar equivalent of protic acid allows for useful reaction rates while minimizing acid use and waste generation.
• the solvent used in the process of this invention can be any inert solvent which when combined with the reactants used in the process of the present invention forms a reaction mixture from which the alcohol produced as a by-product in the process of this invention, such as ethanol, can be promptly separated by distillation.
• the alcohol can be removed as: (a) the alcohol; (b) an azeotrope or mixture of the alcohol and di(C 1 -C 3 alkoxy)methane; (c) an azeotrope or mixture of the alcohol and solvent; or, (d) an azeotrope or mixture of the alcohol, di(C 1 -C 3 alkoxy) methane and solvent.
• non-halogenated solvents such as, aliphatic and aromatic hydrocarbons and alkyl nitriles. More preferred are aliphatic and aromatic hydrocarbons and alkyl nitriles with boiling points between 80 and 150° C. Most preferred are toluene, xylenes, heptane and acetonitrile.
• the alcohol or alcohol-containing component can be distilled from the reaction mixtures using equipment and techniques known to those skilled the art. Equipment and procedures which allow for efficient removal of alcohol while minimizing co-distillation of di(C 1 -C 3 alkoxy) methane and/or solvent are preferred. This can be achieved using conventional fractional distillation equipment.
• reaction of compounds of Formula II with a di(C 1 -C 3 alkoxy)methane is most conveniently run at the boiling point of the reaction mixture at ambient pressure.
• Reaction temperatures need to be at least equal to the boiling point of the by-product alcohol (e.g., ethanol) or of the alcohol containing azeotrope or mixture being removed.
• a reaction temperature from between about 40 and 150° C. that allows for distillation of by-product alcohol. More preferred is a reaction temperature between 60 and 130° C. Most preferred is a reaction temperature between about 80 and 120° C.
• the reaction may also be carried out at elevated or reduced pressure. The use of reduced pressure can be particularly advantageous when using higher boiling solvents.
• the reaction of compounds of Formula III with the compound of Formula IV is conducted at a reaction temperature from about 40 to 120° C. More preferred is a reaction temperature from about 50 to 90° C.
• the reaction can be carried out a ambient pressure, the reaction may also be carried out at elevated or reduced pressure. The use of reduced pressure can be particularly advantageous when using solvents that have boiling points higher than the desired reaction temperature.
• the by-product water be removed from the reaction mixture prior to combination of the reaction mixture with the di(C 1 -C 3 alkoxy)methane. More preferably, the by-product water can be removed by distillation as it is formed.
• di(C 1 -C 3 alkoxy) methane In principle, only one molar equivalent of di(C 1 -C 3 alkoxy) methane is needed. However, sufficient di(C 1 -C 3 alkoxy) methane should be employed so as to allow for losses of di(C 1 -C 3 alkoxy) methane via co-distillation. Any practical amount of the di(C 1 -C 3 alkoxy)methane can be employed in the process of this invention and it can be used as the solvent for the reaction to convert compounds of Formula II to compounds of Formula I. For reasons of economy it is preferable to use between about 1 and 20 equivalents of the di(C 1 -C 3 alkoxy)methane in conjuction with an inert solvent.
• di(C 1 -C 3 alkoxy)methane More preferably between 1 and 10 equivalents of the di(C 1 -C 3 alkoxy)methane can be employed, most preferably between 2 and 7 equivalents.
• the reagents should be combined at a rate such that the by-product alcohol produced is promptly and efficiently removed to avoid the formation of side-reaction products which adversely affect the purity and yield of the desired product.
• a slurry of the hydrazine carboxylate of Formula II containing all or part of the solvent and optionally containing all or part of the protic acid and all or part of the di (C 1 -C 3 alkoxy) methane is added over time to a mixture of the balance of solvent, protic acid and di(C 1 -C 3 alkoxy) methane which has been preheated to the appropriate reaction temperature.
• the di(C 1 -C 3 alkoxy)methane can be added to a mixture of the hydrazine carboyxlates of Formula II, solvent and protic acid which has been preheated to the appropriate reaction temperature.
• the protic acid and the di(C 1 -C 3 alkoxy)methane are combined and heated prior to combination with the hydrazine carboxylate of Formula II, it is preferable to distill out any alcohol produced by the reaction of the acid with the di(C 1 -C 3 alkoxy)methane as it is formed.
• the present invention further pertains to processes for preparing compounds of Formula I comprising: Step (a) preparing compounds of Formula II from compounds of Formula III and Step (b) reacting the compounds of Formula II with a di(C 1 -C 3 alkoxy) methane under conditions which allow for prompt removal of the by-product alcohol by distillation wherein both steps are carried out in the presence of the same protic acid catalyst and inert solvent.
• a compound of Formula I can be further converted to arthropodicidal oxadiazines of Formula VII by
• a 1 L, 4-neck round bottom flask (RBF) was equipped with an overhead stirrer with an oval paddle, thermometer, liquid feed line with an FMI (Fluid Metering Inc.) pump, 10 tray Oldershaw column equipped with a variable takeoff head, condenser and nitrogen inlet, and a heating mantel.
• the system was set up so that temperature could be monitored in the pot, at the 2, 4, 6, 8, 10 trays of the Oldershaw column and at the distillation head. Circulation of chilled water through the condenser was initiated.
• the flask was charged with 50 mL (0.4 mol) of Aldrich diethoxymethane and 100 mL of toluene and heated to reflux. The pot and head temperatures were 106° C.
• the reaction mixture was allowed to cool, and concentrated using a rotary evaporator; the residue was dissolved in ethyl acetate, filtered, and the filtrate concentrated using a rotary evaporator to leave 29.12 grams of oil.
• the oil was slurried with 75 mL of methanol and cooled in an ice bath. The crystals which formed were collected, washed with two 10 mL portions of cold methanol, and dried in a vacuum oven to give 21.0 grams (87% yield) of product which assayed (HPLC, 4.6 ⁇ 250 mm 5-micron, Zorbax® SB-C8 column and eluting at 1.5 mL/min.
• a 1L, 4-neck RBF was equipped with an overhead stirrer with an oval paddle, thermometer, Dean-Stark trap, reflux condenser, and a heating mantel.
• the reactor was charged with 45.7 g (0.183 mol), 96.3% assay of racemic methyl 5-chloro-2,3-dihydro-2-hydroxy-1-oxo-1H-indene-2-carboxylate disclosed in WO 95/29171, 35.1 g (0.21 mol) of 99.4% phenylmethyl hydrazine carboxylate, 3.5 g (0.018 mol) of-para-toluene sulfonic acid monohydrate, and 235 mL of toluene.
• the mixture was heated to reflux for 7 h under a vacuum ( ⁇ 168 to 205 mm) sufficient to maintain the boiling point of the mixture between 65 and 72° C. During this time, 3.4 mL of water was collected in the Dean-Stark trap. Heating was discontinued and the flask returned to atmospheric pressure. On cooling to ambient temperature, the Dean-Stark trap and reflux condenser were removed and replaced with a 5 tray Oldershaw column equipped with a variable takeoff head, condenser and nitrogen inlet. The flask was further equipped with a liquid feed line with an FMI (Fluid Metering Inc.) pump. The system was set up so that temperature could be monitored in the pot, at each tray of the Oldershaw column and at the distillation head.
• FMI Fluid Metering Inc.
• Circulation of chilled water through the condenser was initiated and the reaction mixture heated to reflux.
• the pot and head temperatures were 113° C. and 110° C., respectively.
• Column temperatures (from bottom to top) were 111° C., 110° C., 110° C., 110° C., and 110° C.
• Diethoxymethane (68 mL, 0.54 mol) was then pumped into the reaction mixture at a steady rate over 1 h and 6 min. Once the temperature at the fourth tray (counting from the bottom) of the column dropped below 80° C., takeoff off ethanol/diethoxymethane/toluene distillate was initiated at such a rate as to maintain the temperature at the fourth tray at 77-84° C.
• distillate was slowly collected over 50 min until the temperature at the fourth tray reached 91° C. The rate of take off was then increased and distillation continued until the head temperature reached 108° C. A total of about 104 mL (84.9 g) of distillate was collected. The reaction mixture was allowed to cool, concentrated using a rotary evaporator, the residue dissolved in 210 mL of methanol and cooled in an ice bath.
• a 2 L, 4-neck round bottomed flask was equipped with: an overhead stirrer with an oval paddle; thermometer; a Dean-Stark trap with a reflux condenser and nitrogen inlet; and a heating mantel.
• the reactor was purged with nitrogen and charged with 583 g of toluene, 120.7 g (0.50 mol, 99.68% assay) of 62% ee 5-chloro-2,3-dihydro-2-hydroxy-oxo-1H-indene-2-carboxylate, 94.13 g (0.55 mol) of 97% benzyl carbazate and 9.65 g (0.05 mol) of 98.5% para-toluene sulfonic.
• a 3 L, 4-neck round bottomed flask was equipped with: an overhead stirrer with an oval paddle; thermometer; 5 tray Oldershaw column equipped with a variable take off head, condenser and nitrogen inlet; and a heating mantel.
• the system was set up so that temperature could be monitored in the pot, at each tray of the Oldershaw column and at the distillation head. Circulation of chilled water through the condenser was initiated.
• the flask was charged with 26.3 g (0.25 mol) of Aldrich diethoxymethane and 580 g of toluene and heated to reflux with a boil up of about 35 mL/min.
• the pot and head temperatures were 1111° C. and 102° C., respectively.
• distillate was slowly collected until the temperature at the forth tray reached 101° C. Take off of distillate was discontinued for 10 min during which time the temperature at the forth tray stayed at 101° C. Take off was then resumed at an increased rate until the head temperature reached 109° C. A total of about 328 mL (249 g) of distillate was collected. The reaction mixture was allowed to cool and the solvent then removed by distillation at 35 mm Hg until the pot temperature reached 70° C. Ethanol (360 mL) was then added and the mixture heated to reflux for 1 hour and allowed to cool. When the temperature reached 40° C., 30 mL of water was added and the mixture cooled to about 0° C.
• a 2 L, 4-neck round bottomed flask was equipped with: an overhead stirrer with an oval paddle; thermometer; a Dean-Stark trap with a reflux condenser and nitrogen inlet; and a heating mantel.
• the reactor was purged with nitrogen and charged with 583 g of toluene, 120.7 g (0.50 mol, 99.68% assay) of 62% ee 5-chloro-2,3-dihydro-2-hydroxy-oxo-1H-indene-2-carboxylate, 94.13 g (0.55 mol) of 97% benzyl carbazate and 4.85 g (0.05 mol) of 99% methanesulfonic acid.
• a 3 L, 4-neck round bottomed flask was equipped with: an overhead stirrer with an oval paddle; thermometer; 5 tray Oldershaw column equipped with a variable take off head, condenser and nitrogen inlet; and a heating mantel.
• the system was set up so that temperature could be monitored in the pot, at each tray of the Oldershaw column and at the distillation head. Circulation of chilled water through the condenser was initiated.
• the flask was charged with 26.3 g (0.25 mol) of Aldrich diethoxymethane and 580 g of toluene and heated to reflux with a boil up of about 26 mL/min.
• the pot and head temperatures were 111° C. and 102° C., respectively.
• distillate was slowly collected until the temperature at the forth tray reached 94° C. Take off was then resumed at an increased rate until the head temperature reached 108° C. A total of about 306 mL (234 g) of distillate was collected. The reaction mixture was allowed to cool and the solvent then removed by distillation at 35 mm Hg until the pot temperature reached 71° C. Ethanol (560 mL) was then added and the mixture heated to reflux until the all of the precipitated solids dissolved. The solution was then cooled to about 0° C.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)

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• 1997
  • 1997-01-31 US US09/230,987 patent/USH1950H1/en not_active Abandoned
  • 1997-06-02 IN IN1020CA1997 patent/IN182799B/en unknown
  • 1997-06-16 TW TW86108354A patent/TW337984B/zh active
  • 1997-06-18 ZA ZA975379A patent/ZA975379B/xx unknown
  • 1997-07-31 AU AU39038/97A patent/AU3903897A/en not_active Abandoned
  • 1997-07-31 JP JP10508080A patent/JP2001501916A/ja active Pending
  • 1997-07-31 CN CN97196880A patent/CN1226891A/zh active Pending
  • 1997-07-31 EP EP97936346A patent/EP0922041A1/de not_active Withdrawn
  • 1997-07-31 WO PCT/US1997/013548 patent/WO1998005656A1/en not_active Application Discontinuation
  • 1997-07-31 TR TR1999/00224T patent/TR199900224T2/xx unknown
  • 1997-07-31 BR BR9711003A patent/BR9711003A/pt not_active Application Discontinuation
• 1999
  • 1999-01-28 MX MX9901054A patent/MX9901054A/es unknown

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