title: Synthesis and NMR spectroscopic studies of allylsulfanyl-N1-alkyl-N4-phenyl-1,4-phenylenediamines and their cyclization products, 2,3-dihydro-1-benzothiophenes and thiochromans.
abstract: Regioselective addition of allylthiol at the C-3 position adjacent to the nitrogen carrying the phenyl group of the 1,4-phenylenediamine moiety of compounds 1-4 was rigorously confirmed by 1D NOE difference in combination with gHMBC experiments. The structures of 1,4-phenylenediamines 1-4, allylsulfanyl-N1-alkyl-N4-phenyl-1,4-phenylenediamines 5-8 and cyclization products 9-14 were completely analyzed in both CDCl3 and DMSO-d6 solutions. The 1H and 13C NMR spectra of 10 and 11, which contain two chiral centers, exhibit duplication for several signals, indicating the existence of two diastereomeric forms. The full structures of 5 and 9 were unambiguously confirmed by x-ray crystallography. The 1H and 13C NMR spectra of all compounds were assigned using one- and two-dimensional NMR techniques (APT, DEPT, 1D NOE difference, COSY, NOESY, HETCOR, gHMQC and gHMBC).
authors.affiliation: Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611-7200, USA. katritzky@chem.ufl.edu
authors.forename: Alan R
authors.initials: AR
authors.lastname: Katritzky
authors.forename: Novruz G
authors.initials: NG
authors.lastname: Akhmedov
authors.forename: Mingyi
authors.initials: M
authors.lastname: Wang
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Rostek
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Steel
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis*; D002839:Chromans / Q000138:chemical synthesis*; D018360:Crystallography, X-Ray; D003500:Cyclization; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008968:Molecular Conformation; D010655:Phenylenediamines / Q000138:chemical synthesis*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013876:Thiophenes / Q000138:chemical synthesis*
chemical_list: D000975:Antioxidants; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002839:Chromans; D010655:Phenylenediamines; D013438:Sulfhydryl Compounds; D013876:Thiophenes; C088015:benzothiophene