title: DBU-Mediated Diastereoselective Aldol-Type Cyanomethylation of Isatins.
abstract: An efficient, metal-free approach to 3-substituted 3-hydroxyoxindole by DBU-mediated highly diastereoselective addition of aryl acetonitrile to N-protected isatin under mild conditions has been developed. The reaction proceeds smoothly to produce respective cyanomethylated adducts in good yield and excellent diastereoselectivity. Further transformation of the cyanide group allowed the synthesis of an advance intermediate of corresponding (±) CPC analogue. The mechanistic insight toward the aldol-type cyanomethylation of N-tritylisatin with benzyl cyanide was obtained by DFT calculations.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Delhi , Hauz Khas, New Delhi 110016, India.
authors.forename: V U Bhaskara
authors.initials: VUB
authors.lastname: Rao
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Delhi , Hauz Khas, New Delhi 110016, India.
authors.forename: Krishna
authors.initials: K
authors.lastname: Kumar
authors.affiliation: Physical Chemistry Division, National Chemical Laboratory , Dr. Homi Bhabha Road, Pune 411008, India.
authors.forename: Tamal
authors.initials: T
authors.lastname: Das
authors.affiliation: Physical Chemistry Division, National Chemical Laboratory , Dr. Homi Bhabha Road, Pune 411008, India.
authors.forename: Kumar
authors.initials: K
authors.lastname: Vanka
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Delhi , Hauz Khas, New Delhi 110016, India.
authors.forename: Ravi P
authors.identifier: 0000-0001-5323-5979
authors.initials: RP
authors.lastname: Singh