Background and overview[1]
Carry out ortho-substitution including OMe, OAc and Br on phenylpyridine, and then use [RuCl2 (p-cymene)]2 as a catalyst to perform meta-sulfonation of the ortho-substituted phenylpyridine to obtain The dimer compound, 2-(2-bromophenyl)pyridine, can be used as a pharmaceutical synthesis intermediate. If 2-(2-bromophenyl)pyridine is inhaled, move the patient to fresh air; if there is skin contact, take off contaminated clothing, rinse the skin thoroughly with soap and water, and seek medical attention if you feel unwell; if In case of eye contact, separate eyelids, rinse with running water or saline, and seek medical attention immediately; if ingested, rinse mouth immediately, do not induce vomiting, and seek medical attention immediately.
Preparation[1]
2-(2-Bromophenyl)pyridine is prepared as follows: To a clean, dry spinner tube, add Cu(OAc)2 (1mmol, 0.182g) and the required substrate 2-phenylpyridine (1mmol , 0.143ml), C2Cl4Br2 (2mmol, 0.651g) and acetonitrile (5mL). The reaction was heated to 130°C and stirred for 24 hours, then cooled to room temperature. The reaction mixture was washed with saturated NaHCO3. The NaHSO3 layer was extracted with dichloromethane, filtered through Celite, dried over MgSO4 and the solvent was removed. The crude mixture was then purified by column chromatography. , purified by flash column chromatography, eluting with hexane//NEt3 (4:1:0.01), to obtain the title compound 2-(2-bromophenyl)pyridine as a colorless oil (61% yield). 1HNMR (250MHz, CDCl3) 8.73 (ddd, J=4.9, 1.7, 0.9Hz, 1H), 7.76 (td, J=7.7, 1.8Hz, 1H), 7.69 (dd, J=8.0, 1.0Hz, 1H)) , 7.61 (d, J=7.9Hz, 1H), 7.55 (dd, J=7.6, 1.8Hz, 1H), 7.41 (td, J=7.5, 1.2Hz, 1H), 7.35-7.20 (m, 2H).
Main reference materials
[1]letterSequentialChelation-AssistedAromaticC–HFunctionalisationviaCatalyticmetaSulfonation