title: Selective Halogenation Using an Aniline Catalyst.
abstract: Electrophilic halogenation is used to produce a wide variety of halogenated compounds. Previously reported methods have been developed mainly using a reagent-based approach. Unfortunately, a suitable "catalytic" process for halogen transfer reactions has yet to be achieved. In this study, arylamines have been found to generate an N-halo arylamine intermediate, which acts as a highly reactive but selective catalytic electrophilic halogen source. A wide variety of heteroaromatic and aromatic compounds are halogenated using commercially available N-halosuccinimides, for example, NCS, NBS, and NIS, with good to excellent yields and with very high selectivity. In the case of unactivated double bonds, allylic chlorides are obtained under chlorination conditions, whereas bromocyclization occurs for polyolefin. The reactivity of the catalyst can be tuned by varying the electronic properties of the arene moiety of catalyst.
authors.affiliation: Molecular Catalyst Research Center, Chubu University, 1200 Matsumoto, Kasugai, Aichi 487-8501 (Japan). rsamanta@isc.chubu.ac.jp.
authors.forename: Ramesh C
authors.initials: RC
authors.lastname: Samanta
authors.affiliation: Molecular Catalyst Research Center, Chubu University, 1200 Matsumoto, Kasugai, Aichi 487-8501 (Japan). hyamamoto@isc.chubu.ac.jp.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Yamamoto
mesh_terms: D000577:Amides / Q000737:chemistry; D000814:Aniline Compounds / Q000737:chemistry*; D002384:Catalysis; D054879:Halogenation; D015394:Molecular Structure; D013386:Succinates / Q000737:chemistry
chemical_list: D000577:Amides; D000814:Aniline Compounds; D013386:Succinates; C023650:aniline; C011116:succinamide
keywords: aniline catalyst; aromatic compounds; halo-cyclization; halogenation; heteroaromatic compounds