title: Titanium(IV) chloride-mediated carbon-carbon bond-forming reaction between 3,3-dialkylcyclobutanones and aldehydes.
abstract: Treatment of 3,3-dialkylcyclobutanones with titanium(IV) chloride in the presence of aldehyde gave beta'-chloro-beta-hydroxy ketones in high yields. It was speculated that ring cleavage of the cyclobutanone ring with titanium(IV) chloride gave trichlorotitanium enolate having a tertiary alkyl chloride moiety and then aldol reaction of the titanium enolate proceeded. A trialkylsilylmethyl group at the 2-position of cyclobutanone facilitated the ring cleavage. Synthesis of substituted cyclopentenone from an obtained product is also described.
authors.affiliation: School of Pharmaceutical Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. jimatsuo@p.kanazawa-u.ac.jp
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Matsuo
authors.forename: Mizuki
authors.initials: M
authors.lastname: Kawano
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Okuno
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishibashi
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D020650:Combinatorial Chemistry Techniques; D003503:Cyclobutanes / Q000737:chemistry*; D003517:Cyclopentanes / Q000138:chemical synthesis* / Q000737:chemistry; D006843:Hydrocarbons, Chlorinated / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D017646:Organosilicon Compounds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D000447:Aldehydes; D003503:Cyclobutanes; D003517:Cyclopentanes; D006843:Hydrocarbons, Chlorinated; D007659:Ketones; D017646:Organosilicon Compounds; C007201:cyclopentanone; C025096:titanium tetrachloride; D014025:Titanium