Simple and regioselective bromination of 5,6-disubstituted-indan-1-ones with Br2 under acidic and basic conditions.
Bromination of 5,6-dimethoxyindan-1-one with Br(2) in acetic acid at room temperature produced exclusively the corresponding 2,4-dibromo compound in 95% yield. Reaction of 5,6-dimethoxyindan-1-one with Br(2) in the presence of KOH, K(2)CO(3) or Cs(2)CO(3 )at ~0 degrees C( )gave the monobrominated product 4-bromo-5,6-dimethoxyindan-3-one in 79%, 81% and 67% yield, respectively. 5,6-Dihydroxyindan-1-one was dibrominated on the aromatic ring affording 4,7-dibromo-5,6-dihydroxyindan-1-one both in acetic acid at room temperature and in the presence of KOH at ~0 degrees C. 5,6-Difluoroindan-1-one and 1-indanone were alpha-monobrominated in acetic acid and alpha,alpha-dibrominated under KOH conditions at room temperature.
Choi
Taeyoung
T
College of Pharmacy, Catholic University of Daegu, Hayang, Korea.
Ma
Eunsook
E
D019342:Acetic Acid / Q000737:chemistry; D001966:Bromine / Q000737:chemistry*; D006842:Hydrocarbons, Brominated / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000737:chemistry; D007189:Indans / Q000737:chemistry*; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D017680:Potassium Compounds / Q000737:chemistry; D013696:Temperature
D006842:Hydrocarbons, Brominated; D006878:Hydroxides; D007189:Indans; D017680:Potassium Compounds; D019342:Acetic Acid; D001966:Bromine; C029943:potassium hydroxide
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