Synthesis of isoindoles
A Rh-catalyzed intramolecular condensation of the benzyl azides with α-aryldiazoesters provides isoindoles in very good yields. The reaction proceeded through nucleophilic attack of the organic azide onto a rhodium carbenoid, release of nitrogen gas, and tautomerization of an intermediate imino esters.
J. Zhu, R. Li, Y. Su, P. Gu, J. Org. Chem., 2019, 84, 5813-5820.
A Rh(III)-catalyzed coupling of N-chloroimines with α-diazo-α-phosphonoacetates enables an efficient dechlorinative/dephosphonative access to 2H-isoindoles. In addition, a Ni(II)-catalyzed deesterification enables the complete elimination of reactivity-assisting groups.
B. Qi, L. Li, Q. Wang, W. Zhang, L. Fang, J. Zhu, Org. Lett., 2019, 21, 6860-6863.
α-Azido carbonyl compounds bearing a 2-alkenylaryl moiety at the α-position are promising precursors for synthesis of isoindole and isoquinoline derivatives via 1,3-dipolar cycloaddition of azides onto alkenes and 6π-electrocyclization of N-H imine intermediates, respectively.
B. W.-Q. Hui, S. Chiba, Org. Lett., 2009, 11, 729-732.
A one-pot conversion of isoindolines to 1-arylisoindoles was established from palladium-catalyzed cascade C-H transformations. A dehydrogenation of isoindolines followod by C-H arylation of the isoindoles gives the desired 1-arylisoindoles in good yields.
T. Ohmura, A. Kijima, M. Suginome, Org. Lett., 2011, 13, 1238-1241.