Reaction equation
[CH2:1]([O:6][C:7]1[CH:12]=[CH:11][C:10]([C:13]2[CH:18]=[CH:17][C:16](Br)=[CH:15][CH:14]=2)=[CH:9][CH:8]=1)[CH2:2][CH2:3][CH2:4][CH3:5].C([Li])CCC.C([O:28][B:29](OC(C)C)[O:30]C(C)C)(C)C.Cl>O1CCCC1>[CH2:1]([O:6][C:7]1[CH:12]=[CH:11][C:10]([C:13]2[CH:18]=[CH:17][C:16]([B:29]([OH:30])[OH:28])=[CH:15][CH:14]=2)=[CH:9][CH:8]=1)[CH2:2][CH2:3][CH2:4][CH3:5]Participants
Conditions
- Temperature
- -78 °C
Procedure
To a stirred suspension of 4-(4-n-pentoxyphenyl)bromobenzene (1.0 g, 3.13 mmol) in anhydrous tetrahydrofuran (20 ml) at -78° C. under a nitrogen atmosphere was added n-butyllithium in hexanes (2.5M, 1.32 ml, 3.30 mmol). After a period of 15 min, triisopropylborate (760 μl, 3.30 mmol) was added. Stirring at -78° C. was continued for 15 min and then at 25° C. for 40 min. The mixture was acidified with 0.5N HCl (20 mL) and then partitioned between ether (50 ml) and water (40 ml). The organic phase was washed with water (3×) and brine and dried with magnesium sulfate. The solvent was removed in vacuo to give 4-(4-n-pentoxyphenyl)phenylboronic acid (750 mg) as a white solid: 1H NMR (400 MHZ, DMSO-d6) δ 0.89 (t, 3, J=7.2 Hz), 1.38 (m, 4 ), 1.72 (m, 2), 3.99 (t, 2, J=6.5 Hz), 6.99 (d, 2, J=8.8 Hz), 7.57 (d, 2, J=8.2 Hz), 7.60 (d, 2, J=8.8 Hz), 7.83 (d, 2, J=8.2 Hz).
Workup
- waitwas continued for 15 min
- waitat 25° C. for 40 min
- custompartitioned between ether (50 ml) and water (40 ml)
- washThe organic phase was washed with water (3×) and brine
- dry with materialdried with magnesium sulfate
- customThe solvent was removed in vacuo
Sources & evidence
- ORD record
- ord-29d1296b53a4438d9b7086e9a61b7440
- Source dataset
- uspto-grants-1996_05
- Patent number
- US05516756
Linked notes
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