Hydrochloric Acid → HCID 59445929, compound
Reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:13]=[CH:12][C:11]([Cl:14])=[CH:10][CH:9]=2)=[CH:4][C:3]=1I.C([Mg]Br)(C)C.[B:21](OC)([O:24]C)[O:22]C.Cl>O1CCCC1.C(OCC)C>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:13]=[CH:12][C:11]([Cl:14])=[CH:10][CH:9]=2)=[CH:4][C:3]=1[B:21]([OH:24])[OH:22]Participants
Conditions
- Temperature
- -75 °C
Procedure
To a solution of 4-bromo-4′-chloro-3-iodobiphenyl (8.00 g, 20.40 mmol) in a mixed solvent system of anhydrous diethyl ether (80 ml) and anhydrous tetrahydrofuran (80 ml) at −75° C. is added isopropylmagnesium bromide (31.60 ml, 15% in tetrahydrofuran) dropwise, maintaining the temperature of the reaction mixture below −70° C. When the addition is complete the mixture is stirred at −75° C. for an additional 2 hours, then allowed to warm to −25° C. at which point trimethyl borate (3.15 g, 30.60 mmol) is added dropwise. After the addition is complete the reaction is allowed to warm to room temperature and stir overnight, followed by cooling in an ice-bath and acidification with 2M aqueous hydrochloric acid. The crude product is extracted with ethyl acetate (×3), and the organic fractions are combined, washed with brine, then dried over anhydrous magnesium sulfate. The mixture is filtered and the filtrate is evaporated in vacuo to give a solid which is further triturated with hexanes to afford 4-bromo-4′-chlorobiphenyl-3-yl-boronic acid (5.20 g) as a white solid.
Workup
- temperaturemaintaining the temperature of the reaction mixture below −70° C
- additionWhen the addition
- additionis added dropwise
- additionAfter the addition
- temperatureto warm to room temperature
- stirringstir overnight
- temperatureby cooling in an ice-bath
- extractionThe crude product is extracted with ethyl acetate (×3)
- washwashed with brine
- dry with materialdried over anhydrous magnesium sulfate
- filtrationThe mixture is filtered
- customthe filtrate is evaporated in vacuo
- customto give a solid which
- customis further triturated with hexanes
Sources & evidence
- ORD record
- ord-c34e85d1b7f0455a944cdaecfe5237dd
- Source dataset
- uspto-grants-2015_04
- Patent number
- US09006429B2
Reaction notes
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