title: A study on the conversion of indanones into carbostyrils.
abstract: We have surveyed the utility of Beckmann rearrangement for the conversion of indanones into carbostyrils. Initial attempts at the conversion of 6-methoxy indanone oxime under classical conditions resulted in the formation of the two unusual products: 2-sulfonyloxyindanone and the dimeric product. This unusual rearrangement was also observed by the treatment of some metal triflates species. Further investigation has led to the development of reliable conditions starting from oxime mesylate (not oxime tosylate), in which some strong Lewis acid catalyst (ZrCl(4)) was employed in either a conventional or non-conventional solvent system. The advantage of the new protocol is highlighted by the simple work up and direct isolation of the product in 65% isolated yield.
authors.affiliation: Process Research Laboratory, Second Tokushima Factory, Otsuka Pharmaceutical Co., Ltd., Kawauchi, Tokushima, 771-0182, Japan. torisawa@fact.otsuka.co.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Torisawa
authors.forename: Takao
authors.initials: T
authors.lastname: Nishi
authors.forename: Jun ichi
authors.initials: Ji
authors.lastname: Minamikawa
mesh_terms: D000476:Alkanesulfonates / Q000737:chemistry; D002384:Catalysis; D002712:Chlorides; D006912:Hydroxyquinolines / Q000138:chemical synthesis* / Q000494:pharmacology; D007189:Indans / Q000737:chemistry* / Q000494:pharmacology; D007536:Isomerism; D008698:Mesylates / Q000737:chemistry; D008670:Metals / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry; D010091:Oximes / Q000737:chemistry*; D015363:Quinolones; D012997:Solvents; D015040:Zirconium
chemical_list: D000476:Alkanesulfonates; D002712:Chlorides; D006912:Hydroxyquinolines; D007189:Indans; D008698:Mesylates; D008670:Metals; D009942:Organometallic Compounds; D010091:Oximes; D015363:Quinolones; D012997:Solvents; C010064:carbostyril; D015040:Zirconium; C012077:trifluoromethanesulfonic acid; C429984:zirconium chloride