Catalytic Enantioselective Synthesis of 3, 4, 5‐Trisubstituted Isoxazoline N‐Oxides and Regioselective Synthesis of 3, 4, 5‐Trisubstituted Isoxazoles. Issue 6 (3rd January 2019)

• Record Type: Journal Article
• Authors: Sahoo, Subas Chandra; Pan, Subhas Chandra
• Is Part Of: European journal of organic chemistry. Issue 6(2019)
• Page Start: 1385
• Page End: 1389
• Publication Date: 2019-01-03
• Subjects: Isoxazoline N‐oxides -- α‐Nitrocinnamates -- Organocatalysis -- Regioselectivity -- Isoxazoles; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201801693
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract : An efficient catalytic asymmetric synthesis of 3, 4, 5‐trisubstituted isoxazoline N ‐oxides and regioselective synthesis of 3, 4, 5‐trisubstituted isoxazoles has been described. α‐Nitrocinnamates and α‐nitrobenzophenones were utilized as Michael acceptors respectively. Hydroquinine derived thiourea in combination with cesium carbonate was effective for the synthesis of isoxazoline N ‐oxides whereas stoichiometric di ‐isopropylethylamine (DIPEA) was the best choice for isoxazole synthesis. In both cases a range of aryl and heteroaromatic groups was tolerated. Abstract : A convenient catalytic asymmetric synthesis of 3, 4, 5‐trisubstituted isoxazoline N ‐oxides and regioselective synthesis of 3, 4, 5‐trisubstituted isoxazoles has been developed.