Synthesis of indenes by ytterbium-catalyzed carboalkoxylation/Friedel–Crafts reaction of arylidenecyclopropanes with acetals
作者:Itaru Nakamura、Michiru Kamada、Yoshinori Yamamoto
DOI:10.1016/j.tetlet.2004.02.066
日期:2004.3
arylidenecyclopropanes 1 with acetals 2 afforded the corresponding indene derivatives 3 in good to high yields. For example, in the presence of 10 mol % of Yb(OTf)3 the reaction of 1-phenylbenzylidenecyclopropane 1a with the dimethyl acetals of benzaldehyde 2a, p-tolualdehyde 2b, and p-anisaldehyde 2c gave 1,3-diphenyl-2-(2-methoxyethyl)indene 3a, 2-(2-methoxyethyl)-3-phenyl-1-(p-tolyl)indene 3b, and 1-(p-
lide亚烷基环丙烷1与乙缩醛2的-催化串联碳烷氧基化/ Friedel-Crafts反应可提供高产率或高产率的相应的茚衍生物3。例如,在10mol%的Yb(OTf)3存在下,使1-苯基亚苄基环丙烷1a与苯甲醛2a,对甲苯甲醛2b和对茴香醛2c的二甲基缩醛反应,得到1,3-二苯基-2- (2-甲氧基乙基)茚3a,2-(2-甲氧基乙基)-3-苯基-1-(对甲苯基)茚3b和1-(p-茴香基)-2-(2-甲氧基乙基)-3-苯基茚3c的产率分别为82%,80%和80%。