Categories: Synthesis of N-Heterocycles > benzo-fused N-Heterocycles >
Synthesis of 3,4-dihydroisoquinolones
A simple and robust procedure for the Rh(III)-catalyzed [4+2] cycloaddition of feedstock gases enabled through C-H activation provides a diverse set of 3,4-dihydroisoquinolones and 3-methylisoquinolones in very good yields. The effects of using ethylene and propyne as coupling partners on C-H site selectivity have been explored with a representative set of substrates.
J. S. Barber, D. Kong, W. Li, I. J. McAlpine, S. K. Nair, S. K Sakata, N. Sun, R. L. Patman, Synlett, 2021, 32, 202-206.
Asymmetric C-H functionalization in the presence of cobalt(III)-complexes equipped with trisubstituted chiral cyclopentadienyl ligands enables the synthesis of dihydroisoquinolones from N-chlorobenzamides with a broad range of alkenes. The transformation proceeds with excellent enantioselectivities and high regioselectivities.
K. Ozols, Y.-S. Jang, N. Cramer, J. Am. Chem. Soc., 2019, 141, 5675-5680.
A palladium-catalyzed [4+2] annulation of aryl and alkenyl carboxamides with 1,3-dienes provides 3,4-dihydroisoquinolones and 5,6-dihydropyridinones in very good yields in the presence of air as the terminal oxidant. The method demonstrates good functional group tolerance.
M. Sun, J. Li, W. Chen, H. Wu, J. Yang, Z. Wang, Synthesis, 2020, 52, 1253-1265.
Co(III)-catalyzed regio- and chemoselective redox-neutral C-H annulation of arylamides/acrylamides with 1,3-dienes provides 3,4-dihydroisoquinolinones in good yields. Furthermore, the prepared 3,4-dihydroisoquinolinones can be converted into useful oxirane derivatives in good yields.
B. Ramesh, M. Jeganmohan, J. Org. Chem., 2022, 87, 6902-6909.
A palladium-catalyzed tandem dehydrogenative [4 + 2] annulation of terminal olefins with N-sulfonyl amides provides important heterocyclic compounds bearing a vinyl substituent with high E stereoselectivity in the presence of air as the terminal oxidant.
M. Sun, W. Chen, X. Xia, G. Shen, Y. Ma, J. Yang, H. Ding, Z. Wang, Org. Lett., 2020, 22, 3229-3233.
A dual cobalt- and photoredox-catalyzed HAT hydroarylation of alkenes offers high efficiency in the synthesis of δ-lactams and various other benzo-fused hetercycles compared to established protocols. The proposed mechanism is supported by experiments and DFT calculations.
Y. Yamaguchi, Y. Seino, A. Suzuki, Y. Kamei, T. Yoshino, M. Kojima, S. Matunaga, Org. Lett., 2022, 24, 2441-2445.
A Pd/Xu-Phos-catalyzed asymmetric Heck/Suzuki domino reaction enables the synthesis of chiral disubstituted dihydroisoquinolinones in good yields and excellent enantioselectivities. The reaction shows high functional group tolerance and enables coupling with various aryl/alkenyl boronates.
Q. Chen. S. Li, X. Xie, H. Guo, J. Yang, J. Zhang, Org. Lett., 2021, 23, 4099-4103.
A 3CR of homophthalic anhydride, amines, and aldehydes provides dihydroisoquinolones in good yields and excellent diastereoselectivity.
S. Y. Howard, M. J. Di Maso, K. Shimabukuro, N. P. Burlow, D. Q. Tan, J. C. Fettinger, T. C. Malig, J. E. Hein, J. T. Shaw, J. Org. Chem., 2021, 86, 11599-11607.