Simple and Regioselective Bromination of 5,6-Disubstituted-indan-1-ones with Br2 Under Acidic and Basic Conditions
作者:Taeyoung Choi、Eunsook Ma
DOI:10.3390/12010074
日期:——
Bromination of 5,6-dimethoxyindan-1-one with Br2 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 Br2 in the presence of KOH, K2CO3 or Cs2CO3 at ~0°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°C. 5,6-Difluoroindan-1-one and 1-indanone were α-monobrominated in acetic acid and α,α-dibrominated under KOH conditions at room temperature.
室温下,5,6-二甲氧基茚满-1-酮在乙酸中与 Br2 发生溴化反应,生成了相应的 2,4-二溴化合物,收率为 95%。在 ~0°C 下,在 KOH、K2CO3 或 Cs2CO3 的存在下,5,6-二甲氧基茚满-1-酮与 Br2 反应,生成单溴产物 4-溴-5,6-二甲氧基茚满-3-酮,收率分别为 79%、81% 和 67%。5,6-二羟基茚满-1-酮在芳香环上被二溴化,在室温的乙酸中和在 ~0°C 的 KOH 存在下均可得到 4,7-二溴-5,6-二羟基茚满-1-酮。5,6-二氟茚满-1-酮和 1-茚满酮在乙酸中进行了 α-一溴化反应,并在室温下于 KOH 条件下进行了 α,α-二溴化反应。