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Enantioselective Synthesis of 3‐Acetyl Coumarin Substituted 3‐Hydroxy Oxindoles and Pyranocoumarin Fused Spirooxindoles
Author(s) -
Pratap Reddy Gajulapalli V.,
Kumarswamyreddy Nandarapu,
Lokesh Kanduru,
Kesavan Venkitasamy
Publication year - 2021
Publication title -
chemistryselect
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 34
ISSN - 2365-6549
DOI - 10.1002/slct.202102495
Subject(s) - oxindole , enantioselective synthesis , bifunctional , thiourea , coumarin , chemistry , aldol reaction , organocatalysis , combinatorial chemistry , catalysis , organic chemistry
Enantioselective construction of bioinspired coumarin and oxindole hybrid structures always enduring challenges in organic chemistry due to the generation of asymmetric quaternary/spiro center at the C3 position of oxindole. Herein, we demonstrated a facile enantioselective synthesis of highly functionalized 3,3’‐disubstituted oxindole derivatives containing 3‐acetyl coumarins and pyranocoumarin fused spirooxindoles using L‐ proline derived bifunctional thiourea organocatalyst through Aldol reaction and Michael addition/cyclization. The L‐ proline derived thiourea catalyst well performed with broad substrate scope to produce desired products in very good yields (up to 95 %) and excellent enantioselectivities (up to 99 % ee).