Synthesis of 3-(<i>ω</i>-Hydroxyalkoxy)isobenzofuran-1(3<i>H</i>)-ones by Trifluoroacetic Acid-Mediated Lactonization of<i>tert</i>-Butyl 2-(1,3-Dioxol-2-yl)- or 2-(1,3-Dioxan-2-yl)benzoates
作者:Kazuhiro Kobayashi、Minami Kuroda
DOI:10.1002/hlca.201400123
日期:2014.8
3‐(2‐hydroxyethoxy)‐ or 3‐(3‐hydroxypropoxy)isobenzofuran‐1(3H)‐ones 3 has been developed. Thus, the reaction of 1‐(1,3‐dioxol‐2‐yl)‐ or 1‐(1,3‐dioxan‐2‐yl)‐2‐lithiobenzenes, generated in situ by the treatment of 1‐bromo‐2‐(1,3‐dioxol‐2‐yl)‐ or 1‐bromo‐2‐(1,3‐dioxan‐2‐yl)benzenes 1 with BuLi in THF at −78°, with (Boc)2O afforded tert‐butyl 2‐(1,3‐dioxol‐2‐yl)‐ or 2‐(1,3‐dioxan‐2‐yl)benzoates 2, which
已开发出一种高效的两步法制备3-(2-羟基乙氧基)或3-(3-羟基丙氧基)异苯并呋喃-1(3 H)-酮3。因此,通过1-溴2处理就地产生的1-(1,3-二氧杂-2-基)或1-(1,3-二氧杂-2-基)-2-硫代苯的反应-(1,3-二氧杂-2-基)或1-溴-2-(1,3-二氧杂-2-基)苯1在THF中于-78°带有BuLi,(Boc)2 O得到叔叔2-(1,3-二氧杂-2-基)丁酯或2-(1,3-二氧杂-2-基)苯甲酸丁酯2,随后在CH 3中用CF 3 COOH(TFA)处理后可以轻松进行内酯化2 Cl 2 在0°下以合理的产率得到所需的产物。