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US 8,541,597 B2Granted
Process for preparing biphenyl imidazole compounds
AssigneeTheravance, Inc.
InventorsWeijiang Zhang, Pierre-Jean Colson
Life of this patent
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Abstract
The invention provides processes for preparing intermediates useful for preparing compounds of the formula: or a salt thereof, where R1-3 are as defined in the specification.
Claims5
A process for preparing a compound of formula II:
- or a salt thereof;
- where R1 is —C1-6 alkyl;
- R2 is —O—C1-5alkyl;
- and P is a carboxylic acid protecting group;
- the process comprising the steps of:
- (a) reacting a compound of formula I:
- with a potassium-C1-6alkyl-trifluoroborate reagent in the presence of a palladium-phosphine catalyst to form a compound of formula 3:
- (b) reacting the compound of formula 3 with hydroxylamine or a salt thereof to form a compound of formula 4:
- and
- (c) reacting the compound of formula 4 with a reducing agent to form a compound of formula II or a salt thereof.
7 more elements
Dependencies are inferred from the claim text.