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US 6,441,219 B1Granted
Process for the preparation of 5-and/or 6-substituted-2-hydroxybenzoic acid esters
AssigneeBASF SE
InventorRobert Francis Doehner, Jr.
Life of this patent
Estimating the term…
Abstract
There is provided a single-step process for the preparation of a compound of formula I. Compounds of formula I are useful as starting materials in the synthesis of natural products and in the manufacture of benzophenone fungicidal agents.
Claims12
A process for the preparation of a compound of formula I
- wherein
- R is C1-C6alkyl;
- and
- R1 and R2 are each independently H or C1-C4alkyl which process comprises reacting a compound of formula II
- wherein R is C1-C6alkyl and X is halogen or OCOCH3 with a compound of formula III
- wherein R1 and R2 are each independently H or C1-C4alkyl, in the presence of a C1-C4carboxylic acid salt and a solvent.
3 more elements
A process for the manufacture of a fungicidal benzophenone compound of formula IV
- wherein R1 and R2 are each independently H or C1-C4alkyl;
- and R3, R4, R5 and R6 are each independently C1-C6alkyl which process comprises the following steps:
- a) reacting a compound of formula II
- wherein R is C1-C6alkyl and X is halogen or OCOCH3 with a compound of formula III
- wherein R1 and R2 are as described hereinabove in the presence of a C1-C4carboxylic acid salt and a solvent to form a compound of formula I
- wherein R, R1 and R2 are described hereinabove;
- b) alkylating the formula I compound with a di(C1-C6alkyl)sulfate in the presence of a base to form a compound of formula V
- wherein R3 is C1-C6alkyl;
- c) hydrolyzing the formula V compound in aqueous acid or aqueous base to form the compound of formula VI
- wherein R1, R2 and R3 are described hereinabove;
- d) reacting the formula VI compound with thionyl chloride to form the compound of formula VII
- wherein R1, R2 and R3 are described hereinabove;
- and
- e) reacting the formula VII compound with at least one molar equivalent of a compound of formula VIII
- wherein R4, R5 and R6 are each independently C1-C6 alkyl, in the presence of a Lewis acid and optionally in the presence of a solvent, to give the desired fungicidal formula IV benzophenone compound.
12 more elements
A process for the manufacture of a fungicidal benzophenone one compound of formula K
- wherein R1 is independently H or C1-C4alkyl;
- and R3, R4, R5 and R3, R4, R5 and R6 are each independently C1-C6alkyl which process comprises the following steps:
- a) reacting a compound of formula II
- wherein R is C1-C6alkyl and X is halogen or OCOCH3 with a compound of formula IIIA
- wherein R1 is as described hereinabove in the presence of a C1-C4carboxylic acid salt and a solvent to form a compound of formula IA
- wherein R, R1 and R2 are described hereinabove;
- b) alkylating the formula I compound with a di(C1-C6alkyl)sulfate in the presence of a base to form a compound of formula VA
- wherein R3 is C1-C6alkyl;
- c) brominating the formula VA compound with a brominating agent optionally in the presence of a base, to form a compound of formula L
- wherein R, R1 and R3 are described hereinabove;
- d) hydrolyzing the formula L compound in an aqueous acid or aqueous base to form a compound of formula M
- wherein R1 and R3 are described hereinabove;
- e) reacting the formula M compound with thionyl chloride to form the compound of formula N
- wherein R1 and R3 are described hereinabove;
- and
- f) reacting the formula N compound with at least one molar equivalent of a compound of formula VIII
- wherein R4, R5 and R6 are each independently C1-C6alkyl, in the presence of a solvent, to give the desired fungicidal formula K benzophenone compound.
14 more elements
Dependencies are inferred from the claim text.