Palladium-catalyzed allylation and deacylative allylation of 3-acetyl-2-oxindoles with allylic alcohols
作者:Aitor Ortega-Martínez、Rocco de Lorenzo、José M. Sansano、Carmen Nájera
DOI:10.1016/j.tet.2017.11.041
日期:2018.1
Pd-catalyzed allylation of 3-acetyl-2-oxindoles with allyl alcohol is performed using 3 mol% of Pd(dba)2, rac-BINAP and BINOL phosphoric acid as catalytic mixture. This procedure allows the in situ synthesis of 3-allyl-2-oxindole by adding Triton B to the reaction mixture. The deacylative allylation of 3-acetyl-3-methyl-2-oxindoles with allylicalcohols is carried out with 3 mol% of Pd(OAc)2, dppp and 1.5
使用3 mol%的Pd(dba)2,rac-BINAP和BINOL磷酸作为催化混合物,进行3-乙酰基-2-氧吲哚与烯丙醇的Pd催化烯丙基化反应。该方法允许通过将Triton B加入反应混合物中原位合成3-烯丙基-2-恶吲哚。用3mol%的Pd(OAc)2,dppp和1.5当量进行3-乙酰基-3-甲基-2-氧吲哚与烯丙基醇的脱酰基烯丙基化。LiO t Bu作为碱,以良好的产率提供了相应的3,3-二取代的2-氧吲哚。可以将两种方法结合起来用于制备不对称的3,3-二烯丙基化的2-氧吲哚,例如化合物7。DaA必须在无氧条件下进行,以避免竞争性形成3-烷基-3-羟基-2-吲哚。通过在室温下在空气中用LiOEt对3-烷基化的3-乙酰基-2-氧吲哚进行3-烷基化的3-乙酰基-2-氧吲哚的酰基化反应,可以容易地获得后面的化合物。
Synthesis of oxindolesvia visible light photoredox catalysis
2-Electron-withdrawing-group-substituted 2-bromoanilides can be converted to the corresponding 3,3-disubstituted oxindoles with high efficiency under visible light irradiation by using fac-Ir(ppy)3 as the photoredox catalyst. This protocol is suitable for the synthesis of oxindoles with chloro and bromo atoms attached to the phenyl ring.
在可见光照射下,通过将2-抽电子基团取代的2-溴苯胺可以高效转化为相应的3,3-二取代的羟吲哚。 fac -Ir(ppy)3作为光氧化还原催化剂。该方案适用于合成具有连接在苯环上的氯和溴原子的羟吲哚。
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>n</mml:mi></mml:math>-selective Tsuji–Trost allylation promoted by a recyclable TSIL-palladium complex