Platinum-Catalyzed, One-Pot Tandem Synthesis of Indoles and Isoquinolines via Sequential Rearrangement of Amides and Aminocyclization
作者:Noriko Okamoto、Kei Takeda、Reiko Yanada
DOI:10.1021/jo101347f
日期:2010.11.19
By using platinum(II) chloride as a Lewis acid catalyst, concise and efficient syntheses of indole carbamates, 1,2-dihydroisoquinoline carbamates, macrocyclic indole carbamates, indole ureas, and indole phosphoranes have been achieved via tandem Hofmann-type rearrangement of 2-alkynylbenzamides and 2-alkynylbenzylamides, nucleophilic addition of alcohols and amines to the isocyanate intermediates,
Concise One-Pot Tandem Synthesis of Indoles and Isoquinolines from Amides
作者:Noriko Okamoto、Yoshihisa Miwa、Hideki Minami、Kei Takeda、Reiko Yanada
DOI:10.1002/anie.200904960
日期:2009.12.14
Heterocyclic hot pot: Platinum(II)‐catalyzed syntheses of indoles and isoquinolines from isocyanates, which are derived from a Hofmann‐type rearrangement of amides using a hypervalent iodine reagent, are described. C2‐symmetric macrocyclic bis(indole)s can also be synthesized from transannulation of C2‐symmetric macrocyclic bis(alkyne carbamate) intermediates.
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。