A palladium-catalyzed cyclization–carbonylation of 2-alkynylprimarybenzamides 1 afforded methyl 3-substituted 1-methoxyisoquinoline-4-carboxylates 6 in good to moderate yields. In the case of mesylate 1r, 12 was obtained directly via a cyclization–carbonylation–cyclization cascade. Compounds 6 were converted to isoquinolin-1(2H)-ones 8 in good yields under microwave irradiation. In the case of the
钯催化的 2-炔基伯苯甲酰胺1的环化-羰基化反应以良好至中等的收率得到 3-取代的 1-甲氧基异喹啉-4-羧酸甲酯6 。就甲磺酸酯1r而言, 12是通过环化-羰基化-环化级联直接获得的。在微波辐射下,化合物6以良好的产率转化为异喹啉-1(2 H )-酮8 。在甲磺酸酯6q的情况下,以良好的产率获得三环异喹啉酮10 。噻吩-2-甲酰胺衍生物的反应也进展顺利。
Stereoselective Synthesis of 3-Methyleneisoindolin-1-ones via Base-Catalyzed Intermolecular Reactions of Electron-Deficient Alkynes with <i>N</i>-Hydroxyphthalimides
作者:Xin Chen、Fei-Fei Ge、Tao Lu、Qing-Fa Zhou
DOI:10.1021/acs.joc.5b00002
日期:2015.3.20
Highly stereoselective intermolecular reactions of electron-deficient alkynes with N-hydroxyphthalimides for efficient construction of N-unprotected 3-methyleneisoindolin-1-ones have been developed through base catalytic strategies. The reaction of alkynoates with N-hydroxyphthalimides catalyzed by Bu3P in DMF at 150 degrees C gave the corresponding 3-methyleneisoindolin-1-ones with a (Z)-configuration, while the reaction of alkynoates with N-hydroxyphthalimides catalyzed by K2CO3 in DMF at 60 degrees C gave the corresponding 3-methyleneisoindolin-1-ones with an (E)-configuration, and (Z)-3-methyleneisoindolin-1-ones were obtained when alkyne ketones reacted with N-hydroxyphthalimide.
Oxidative Alkenylation/Annulation of Benzimidates<i>via</i>Ruthenium(II)-Catalyzed CH Activation to Generate 3-Methyleneisoindolin-1-ones
作者:Xing Guang Li、Min Sun、Kai Liu、Pei Nian Liu
DOI:10.1002/adsc.201400727
日期:2015.2.9
AbstractA novel ruthenium‐catalyzed oxidative alkenylation/annulation cascade reaction is described for synthesizing 3‐methyleneisoindolin‐1‐ones. In the protocol, the NH imidate is applied efficiently as a directing group in ruthenium‐catalyzed CH activation, generating various 3‐methyleneisoindolin‐1‐ones with high regio‐ and stereoselectivity in moderate to good yields.magnified image