Efficient Asymmetric Synthesis of 4H-Chromene Derivatives through a Tandem Michael Addition-Cyclization Reaction Catalyzed by a Salen-Cobalt(II) Complex

• Published in: European Journal of Organic Chemistry Vol. 2011; no. 1; pp. 137 - 142
• Main Authors: Dong, Zhenhua, Liu, Xiaohua, Feng, Juhua, Wang, Min, Lin, Lili, Feng, Xiaoming
• Format: Book Review Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.01.2011; WILEY‐VCH Verlag; Wiley; Wiley-VCH
• Subjects: Asymmetric synthesis; Biological activity; Chemistry; Chemistry, Organic; Cycli­zation; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with o, s, se, te hetero atom and condensed derivatives; Michael addition; Organic chemistry; Physical Sciences; Preparations and properties; Science & Technology; Tandem reactions; Michael addition; APOPTOSIS; SERIES; ENANTIOSELECTIVE SYNTHESIS; Tandem reactions; 4-ARYL-4H-CHROMENES; Biological activity; DISCOVERY; Asymmetric synthesis; Cyclization; KETO-ESTERS; THROUGHPUT SCREENING ASSAY; SALEN; INHIBITORS; ACCESS; Divalent metal Complexes; Catalytic reaction; Transition element complexes; Nitrile; Enantioselectivity; Chiral compound; Transition metal Complexes; Air; Oxygen heterocycle; Tandem reaction; Ketone; Amine; Addition reaction; Enantiomeric excess; Chemical synthesis; Cobalt II Complexes
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.201001151

The asymmetric synthesis of 2‐amino‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromene derivatives was achieved through a tandem Michael addition–cyclization reaction of easily available cyclohexane‐1,3‐dione and ethyl 2‐cyano‐3‐phenylacrylates. Moderate to good yields (up to 81 %) and high enantioselectivities (up to 89 % ee) were obtained with a chiral salen–cobalt(II) complex. This process was air tolerant and easily performed, which provides an efficient method for the synthesis of chiral 4H‐chromene derivatives. The asymmetric synthesis of 2‐amino‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromene derivatives was achieved through a tandem Michael addition–cyclization reaction of easily available cyclohexane‐1,3‐dione and ethyl 2‐cyano‐3‐phenylacrylates catalyzed by a chiral salen–cobalt(II) complex with moderate to good yields (up to 81 %) and high enantioselectivities (up to 89 % ee).