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Titanium(IV) chloride-mediated carbon-carbon bond-forming reaction between 3,3-dialkylcyclobutanones and aldehydes
Jun-ichi Matsuo1, Mizuki Kawano, Ryosuke Okuno
1School of Pharmaceutical Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. jimatsuo@p.kanazawa-u.ac.jp
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.
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