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US3972887A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing phosphorothioates and phenylphosponothioates

Assignee: Dow Chemical Co
•
Filing: 1975-06-12
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Granted: 1976-08-03
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Expires: 1995-06-12
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Abstract

Abstract Quaternary ammonium salts are novel catalysts in the process of reacting an alkali metal phenate, pyridinate or pyrimidinate with an O,O-dialkyl phosphorochloridothioate or O-alkyl phenylphosphonochloridothioate to produce the corresponding phosphorothioates and phenylphosphonothioates. The process is conducted under alkaline conditions in a liquid reaction medium. As an example, O,O-diethyl O-(3,5,6-trichloro-2-pyridyl)-phosphorothioate is prepared in excellent yields and purity by reacting solid particulate sodium 3,5,6-trichloropyridinate with O,O-diethyl phosphorochloridothioate dissolved in a stirred methylene chloride reaction medium in the presence of a catalytic amount of benzyltriethylammonium chloride.

Inventors

  • 👤 Harold H. Freedman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 14:46
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/06; C07F9/16; C07F9/165; C07F9/547; C07F9/553; C07F9/576; C07F9/58; C07F9/645; C07F9/6509; C07F9/650952

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 193 words
In the process of preparing a compound corresponding to the formula ##EQU7##wherein: R 1 and R 2 are each independently lower alkyl; and ##SPC2## wherein: n is 0, 1, 2 or 3; and X is nitro, cyano, halo, lower alkyl, lower alkoxy, lower alkylthio or lower alkylsulfinyl, with the proviso that R does not bear more than one nitro group, lower alkylthio group or lower alkylsulfinyl group; by reacting in an inert organic liquid medium under alkaline conditions and with efficient blending (a) a compound corresponding to the formula R--O -M + or M + -O--C 6 H 4 --S--C 6 H 4 --O -M + in solid particulate form with (b) a compound dissolved in said liquid medium and corresponding to the formula ##EQU8##wherein M is an alkali metal and R, R 1 and R 2 have the aforesaid meaning; the improvement consisting of conducting the process in the presence of a small but catalytic amount of a quaternary ammonium salt having a minimum solubility of at least 1 weight percent in the liquid reaction medium at 25°C and having a total aggregate carbon content of at least about 10 carbon atoms.
Claim 2
Dependent Claim 193 words
In the process of preparing a compound corresponding to the formula ##EQU7##wherein: R 1 and R 2 are each independently lower alkyl; and ##SPC2## wherein: n is 0, 1, 2 or 3; and X is nitro, cyano, halo, lower alkyl, lower alkoxy, lower alkylthio or lower alkylsulfinyl, with the proviso that R does not bear more than one nitro group, lower alkylthio group or lower alkylsulfinyl group; by reacting in an inert organic liquid medium under alkaline conditions and with efficient blending (a) a compound corresponding to the formula R--O -M + or M + -O--C 6 H 4 --S--C 6 H 4 --O -M + in solid particulate form with (b) a compound dissolved in said liquid medium and corresponding to the formula ##EQU8##wherein M is an alkali metal and R, R 1 and R 2 have the aforesaid meaning; the improvement consisting of conducting the process in the presence of a small but catalytic amount of a quaternary ammonium salt having a minimum solubility of at least 1 weight percent in the liquid reaction medium at 25°C and having a total aggregate carbon content of at least about 10 carbon atoms.
Claim 3
Dependent Claim 124 words
The process defined in claim 1 wherein (1) is a quaternary ammonium salt of the formula R 1 'R 2 'R 3 'R 4 'N +A - , wherein R 1 '-R 4 ' are each independently hydrocarbyl groups of from 1 to about 12 carbon atoms, or R 1 ' is joined with R 2 ' to form a 5- or 6-membered heterocyclic ring wherein one member of said heterocyclic ring is a quaternized nitrogen atom, a second member of said heterocyclic ring is an atom of carbon, nitrogen, oxygen or sulfur, and the remaining members of said heterocyclic ring are carbon atoms; and A - is an anion; said quaternary ammonium salt having a maximum carbon content of about 31 carbon atoms.
Claim 4
Dependent Claim 18 words
The process defined in claim 2 wherein said quaternary ammonium salt is a benzyltrimethyl-, benzyltriethyl-, or tetra-n-butylammonium salt.
Claim 5
Dependent Claim 17 words
The process defined in claim 3 wherein said quaternary ammonium salt is benzyltriethylammonium chloride or tetra-n-butylammonium bisulfate.
Claim 6
Dependent Claim 33 words
The process defined in claim 1 wherein said ammonium salt is present in an amount of from about 0.25 to about 20 mole percent, based on the combined moles of (a) and (b).
Claim 7
Dependent Claim 21 words
The process defined in claim 5 wherein the amount of said ammonium is from about 0.5 to about 10 mole percent.
Claim 8
Dependent Claim 16 words
The process defined in claim 1 wherein R 1 and R 2 are methyl or ethyl.
Claim 9
Dependent Claim 10 words
The process defined in claim 7 wherein R is ##SPC3##
Claim 10
Dependent Claim 33 words
The process defined by claim 8 wherein said quaternary ammonium catalyst is a benzyltrimethyl-, benzyltriethyl- or tetra-n-butylammonium salt and is present in an amount of from about 0.25 to about 20 mole percent.
Claim 11
Dependent Claim 32 words
The process defined in claim 1 wherein said quaternary ammonium catalyst is benzyltriethylammonium chloride or tetra-n-butylammonium bisulfate and is present in an amount of from about 0.5 to about 10 mole percent.
Claim 12
Dependent Claim 14 words
The process defined in claim 10 wherein said process is conducted in methylene chloride.
Claim 13
Dependent Claim 27 words
The process defined in claim 1 wherein (a) is sodium O-3,5,6-trichloro-2-pyridinate and (b) is O,O-diethyl phosphorochloridothioate; and the reaction temperature is from about 40° to about 60°C.

References Cited (Backward Citations)

GB1227144A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-08-03 1980-02-02 1980-08-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-08-03 1984-02-02 1984-08-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-08-03 1988-02-02 1988-08-03 $7700.00 Window Closed / Lapsed

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