title: Organocatalytic Asymmetric Michael/Hemiketalization/Retro-aldol Reaction of α-Nitroketones with Unsaturated Pyrazolones: Synthesis of 3-Acyloxy Pyrazoles.
abstract: An organocatalytic asymmetric cascade Michael/hemiketalization/retro-aldol reaction between unsaturated pyrazolones and α-nitroketones is described. A bifunctional thiourea catalyst was found to be efficient for this reaction. With 10 mol % of catalyst, high yields as well as excellent enantioselectivities are attained for a variety of 3-acyloxy pyrazoles under mild reaction conditions.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati , North Guwahati, Assam 781039, India.
authors.forename: Rajendra
authors.initials: R
authors.lastname: Maity
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati , North Guwahati, Assam 781039, India.
authors.forename: Chandan
authors.initials: C
authors.lastname: Gharui
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati , North Guwahati, Assam 781039, India.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Sil
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati , North Guwahati, Assam 781039, India.
authors.forename: Subhas Chandra
authors.identifier: 0000-0002-7581-1831
authors.initials: SC
authors.lastname: Pan