Efficient synthesis of isoindoles using supercritical carbon dioxide

Diels–Alder Cycloaddition Reactions in Sustainable Media

“…Ito and coworkers disclosed a protocol for the synthesis of isoindoles from bicyclopyrroles by a retro-Diels-Alder reaction in scCO 2 [84]. In general, bicyclopyrroles were converted into the corresponding isoindoles in high yields; however, in some cases, the instability associated with the exomethylenic structure causes the decomposition of the isoindole derivatives.…”

Synthesis of Isoindoles from Intramolecular Condensation of Benzyl Azides with α-Aryldiazoesters

“…All of the experiments were performed with 0.2 mmol of 1a in the presence of 1 mol % copper salts or rhodium salts in dichloromethane at room temperature (entries 1–4, Table ). To our delight, the known isoindole 2a could be observed with each case. Rh 2 (oct) 4 was demonstrated as the best catalyst, and isoindole 2a was isolated in 97% yield.…”

“…The lactones 3b , 3c , 3e , 3f , 3g , 3h , 3i , 3k , 3l were prepared from the known dicarboxylic acids. The isoindoles 2a , 2k , and 2l had been previously prepared by Ito’s group . All of the reaction of the benzyl azides with α-aryldiazoesters was carried out in dry reaction vessels or flasks under a positive pressure of nitrogen or argon.…”

1,2-Dihaloalkenes in Metal-Catalyzed Reactions

“…29 These substrates were utilized in the construction of skeletons of complex polycyclic molecules like 13H-indeno[1,2-l]phenanthrenes 77, 29e spiroketals 78 29a and 79, 29b 2H-chromenes 80, 29c 6,9-dihydropyrido[1,2-a]indoles 81, 29d coumarins 82, 30 and isoindoles 83. 31 Incidentally, Ito and co-workers were also able to synthesize dimethylated analogues of 83 in 65% yield. 31 Since 2000, only one example of diarylation using a 1,2dichloroalkene has been found.…”

“…31 Incidentally, Ito and co-workers were also able to synthesize dimethylated analogues of 83 in 65% yield. 31 Since 2000, only one example of diarylation using a 1,2dichloroalkene has been found. In 2010, Sasaki and coworkers showed that 2,3-dichloro-1,4-naphthoquinone (84) was diarylated with boronate ester 85 to produce 86 (Scheme 24).…”