293744-62-4Relevant academic research and scientific papers
Phosphazene Superbase-Mediated Regio- and Stereoselective Iodoaminocyclization of 2-(1-Alkynyl)benzamides for the Synthesis of Isoindolin-1-ones
Mehta, Saurabh,Brahmchari, Dhirendra
, p. 5492 - 5503 (2019/05/10)
Phosphazene superbase P4-t-Bu mediated iodoaminocyclization of 2-(1-alkynyl)benzamides is reported. The reaction works under ambient conditions and instantaneously results in the synthesis of isoindolin-1-ones in 65-97% yields, in a regio- and stereoselective manner. The exclusive formation of products with Z-geometry (across the exo C?C bond) has been confirmed through X-ray crystallography. The methodology also provides an easy access to aristolactams, an important class of natural products. This has been successfully demonstrated by synthesizing two aristolactam derivatives (including Cepharanone B).
Regio- and Stereoselective Synthesis of Isoindolin-1-ones through BuLi-Mediated Iodoaminocyclization of 2-(1-Alkynyl)benzamides
Brahmchari, Dhirendra,Verma, Akhilesh K.,Mehta, Saurabh
supporting information, p. 3339 - 3347 (2018/03/23)
A simple and straightforward synthesis of isoindolin-1-ones is reported. Exclusive N-cyclization of the amide functional group, an ambident nucleophile, was accomplished for the cyclization of 2-(1-alkynyl)benzamides using n-BuLi-I2/ICl. The methodology works with the primary amide and affords the desired isoindolinones in yields of 38-94%. Interestingly, the isolated products exhibit a Z-stereochemistry across the C=C double bond. The reaction mechanism involving the formation of either a vinylic anion or an intimate ion pair intermediate is proposed.
Palladium-catalysed heteroannulation with terminal alkynes: A highly regio- and stereoselective synthesis of (Z)-3-aryl(alkyl)idene isoindolin-1- ones
Kundu, Nitya G.,Khan, M. Wahab
, p. 4777 - 4792 (2007/10/03)
A highly regio- and stereoselective method for the synthesis of (Z)-3- aryl(alkyl)idene isoindolin-1-ones through palladium-copper catalysis is described. 2-Iodobenzamide 1 and its substituted derivatives 2-10 were reacted with terminal alkynes 11-19 in the presence of (PPh3)2PdCl2, CuI, and Et3N in DMF mostly at 80°C for 16 h to yield the 2-alkynyl substituted benzamides 20-38, 40-45, 77 which could then be cyclised with NaOEt in EtOH to the 3-aryl(alkyl)idene isoindolin-1-ones 46-49, 51, 53-55, 57, 59-71, 73 and 75. In certain cases, the isoindolin-1-ones 50, 52, 56 and 58 could be directly obtained by the palladium-catalysed reactions. (C) 2000 Elsevier Science Ltd.
A highly regio and stereoselective synthesis of (Z)-3- aryl(alkyl)idene isoindolin-1-ones via palladium catalyzed annulation of terminal alkynes
Khan, M. Wahab,Kundu, Nitya G.
, p. 1435 - 1437 (2007/10/03)
o-Iodobenzamide or its N-substituted derivatives 4-10 and terminal alkynes 11-17 reacted in DMF in the presence of bis(triphenylphosphine)palladium(II)chloride, cuprous iodide and triethylamine leading to (Z)-3- arylidene isoindolin-1-ones (22, 24, 27 and 28) or o-alkynyl N-substituted benzamides (I). The latter could be cyclised with sodium in ethanol in a completely regio and stereoselective manner to (Z)-3-aryl(alkyl)idene isoindolin-1-ones 18-35.
