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US 7,009,062 B2Granted
Process for the preparation of flavone derivatives
AssigneeMerck Patent GmbH
InventorsHerwig Buchholz, Sophie Perruchon
Life of this patent
Estimating the term…
Abstract
The invention relates to a process for the preparation of flavone derivatives in which a 2-hydroxyacetophenone compound is metallated using a lithium compound at low temperatures and subsequently reacted with a keto compound, and where the ratio of the molar equivalents of lithium compound to the 2-hydroxyacetophenone compound functional groups to be metallated is from 1 to 1.2. The resultant β-diketone compound is subsequently cyclized with warming in an acidic medium.
Claims10
A process for preparing a compound of the formula:
- comprising metallating a compound of the formula:
- wherein R1–R4, are, independently, hydrogen or a group of hydroxyl, alkyl, alkenyl, ether, ester, aryl, O-glycosyl, alkoxy, alkenoxy, aryloxy, halogen, nitro or amino, and/or any two adjacent R1–R4 may combine to form a ring system, and R is hydrogen, an alkoxy group or an optionally substituted phenyl group, with an inorganic lithium compound, and
- subsequently reacting the metallated compound with a keto compound of the formula:
- wherein R6–R10 are, independently, hydrogen or a group of hydroxyl, alkyl, alkenyl, ether, ester, aryl, O-glycosyl, alkoxy, alkenoxy, aryloxy, halogen, nitro or amino, and/or any two adjacent R6–R10 may combine to form a ring system, and R5 is a halide, alkoxy or ester group, wherein the ratio of molar equivalents of the lithium compound to the functional groups to be metallated on the 2-hydroxyacetophenone compound is 1–1.2.
1 more element
A process for preparing a compound of the formula:
- comprising metallating a compound of the formula:
- wherein R1–R4, are, independently, hydrogen or a group of hydroxyl, alkyl, alkenyl, ether, ester, aryl, O-glycosyl, alkoxy, alkenoxy, aryloxy, halogen, nitro or amino, and/or any two adjacent R1–R4 may combine to form a ring system, and R is hydrogen, an alkoxy group or an optionally substituted phenyl group, with an inorganic lithium compound, and
- subsequently reacting the metallated compound with a compound of the formula:
- wherein R6–R10 are, independently, hydrogen or a group of hydroxyl, alkyl, alkenyl, ether, ester, aryl, O-glycosyl, alkoxy, alkenoxy, aryloxy, halogen, nitro or amino, and/or any two adjacent R6–R10 may combine to form a ring system, and R5 is a halide, alkoxy or ester group.
1 more element
Dependencies are inferred from the claim text.