title: Stereoselective synthesis of 1,2-diamine containing indolines by a conjugate addition nitro-Mannich reaction.
abstract: A conjugate addition nitro-Mannich reaction followed by nitro reduction and intramolecular N-arylation gives diastereomerically pure substituted 1,2-diamine containing indolines. Placing the N-arylation cyclisation handle on the imine precursor derived from an ortho-bromine substituted aromatic aldehyde gave the corresponding β-nitroamines in 55-72% yields as single diastereoisomers. Nitro reduction was effected with modified quantities of Zn/HCl and a subsequent Pd(0) catalysed Buchwald Hartwig cyclisation gave indoline products in 40-70% yields as single diastereoisomers.
authors.affiliation: Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK. j.c.anderson@ucl.ac.uk.
authors.forename: James C
authors.initials: JC
authors.lastname: Anderson
authors.forename: Ian B
authors.initials: IB
authors.lastname: Campbell
authors.forename: Sebastien
authors.initials: S
authors.lastname: Campos
authors.forename: Jonathan
authors.initials: J
authors.lastname: Shannon
authors.forename: Derek A
authors.initials: DA
authors.lastname: Tocher
mesh_terms: D060326:Chemistry Techniques, Synthetic; D003500:Cyclization; D003959:Diamines / Q000138:chemical synthesis* / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D009574:Nitro Compounds / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D003959:Diamines; D007211:Indoles; D009574:Nitro Compounds; D010165:Palladium; C057812:indoline