865086-04-0Relevant academic research and scientific papers
Formation of 4,5,6,7-tetrahydroisoindoles by palladium-catalyzed hydride reduction
Hou, Duen-Ren,Wang, Ming-Shiang,Chung, Ming-Wen,Hsieh, Yih-Dar,Tsai, Hui-Hsu Gavin
, p. 9231 - 9239 (2008/03/13)
(Chemical Equation Presented) Substituted 1,3-dihydro-2H-isoindoles (2, isoindolines) were prepared and subjected to palladium-catalyzed formate reduction. Alkyl isoindolines were reduced to 4,5,6,7-tetrahydro-2H-isoindoles (1). Only partial reduction was observed for 5-methoxyisoindoline, and 4-methoxy-, 5-carbomethoxy-, amino-, and amidoisoindolines were inert to the reaction. Halogen-substituted isoindolines were dehalogenated and reduced to 4,5,6,7-tetrahydro-2H-isoindoles. Isoindole 24 was also reduced to a mixture of an isoindoline and a 4,5,6,7-tetrahydro-2H-isoindole. In contrast, 2,3-dihydro-1H-indoles 21 underwent dehydrogenation to give thermodynamically stable indoles. Theoretical calculations show the significant difference in aromaticity between isoindoles and indoles, corresponding to the observed differences in reactivities. Tetrahydro-2H-isoindoles 1 were oxidized to 4,5,6,7-tetrahydroisoindole-1,3-diones in the presence of NBS and air.
New formation of 4,5,6,7-tetrahydroisoindoles
Hou, Duen-Ren,Hsieh, Yih-Dar,Hsieh, Yi-Wei
, p. 5927 - 5929 (2007/10/03)
The high-yield syntheses of 4,5,6,7-tetrahydro-isoindoles from N-substituted isoindolines under palladium catalyzed hydrogenation conditions are reported. Mechanistic study with deuterated and saturated substrates show extensive H/D exchange and the essence of aromaticity in this transformation.
