4-Toluenesulfonyl chloride → 2,2,4,6,7-Pentamethyl-5-(p-toluenesulfonylamino)-2,3-dihydrobenzofuran

HRID 1493049Notes

Reaction equation

[NH2:1][C:2]1[C:3]([CH3:15])=[C:4]([CH3:14])[C:5]2[O:9][C:8]([CH3:11])([CH3:10])[CH2:7][C:6]=2[C:12]=1[CH3:13].[C:16]1([CH3:26])[CH:21]=[CH:20][C:19]([S:22](Cl)(=[O:24])=[O:23])=[CH:18][CH:17]=1.ClCCl.C(OC(C)C)(C)C>N1C=CC=CC=1>[CH3:11][C:8]1([CH3:10])[CH2:7][C:6]2[C:12]([CH3:13])=[C:2]([NH:1][S:22]([C:19]3[CH:20]=[CH:21][C:16]([CH3:26])=[CH:17][CH:18]=3)(=[O:24])=[O:23])[C:3]([CH3:15])=[C:4]([CH3:14])[C:5]=2[O:9]1

Participants

Conditions

Temperature: 50 °C

Procedure

5-Amino-2,2,4,6,7-pentamethyl-2,3-dihydrobenzofuran (2.00 g, 9.74 mmol) and p-toluenesulfonyl chloride (2.04 g, 10.7 mmol) were dissolved in pyridine (30 ml) and stirred at 50° C. for 1 hour. The reaction mixture was concentrated under reduced pressure and the residue was dissolved in chloroform. The mixture was washed with 1N hydrochloric acid and saturated saline and dried and then the solvent was distilled off under reduced pressure. The residue was purified by column chromatography on silica gel (hexane-ethyl acetate, 97:3). The crude crystals were recrystallized from dichloromethane-isopropyl ether to obtain the desired compound (2.41 g, yield: 68.8% yield), m.p. 219°-220° C. (dichloromethane-isopropyl ether).

Workup

concentrationThe reaction mixture was concentrated under reduced pressure
dissolutionthe residue was dissolved in chloroform
washThe mixture was washed with 1N hydrochloric acid and saturated saline
customdried
distillationthe solvent was distilled off under reduced pressure
customThe residue was purified by column chromatography on silica gel (hexane-ethyl acetate, 97:3)
customThe crude crystals were recrystallized from dichloromethane-isopropyl ether

Sources & evidence

ORD record: ord-fe23a556e6a14d6ba37581c9a879a838
Source dataset: uspto-grants-1994_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05376681

Reaction notes

Loading…