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Ring expansion/homologation--aldehyde condensation cascade using tert-trihalomethylcarbinols.

ABSTRACT: Treatment of cyclic tert-trihalomethylcarbinols with CrCl(2) in THF/HMPA in the presence of aryl or aliphatic aldehydes initiates a cascade sequence of one carbon ring expansion-olefination affording conjugated exocyclic ketones. Acyclic tert-trihalomethylcarbinols undergo a comparable cascade of one carbon homologation-olefination.

SUBMITTER: Falck JR

PROVIDER: S-EPMC2517229 | biostudies-literature | 2006 Sep

REPOSITORIES: biostudies-literature

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Ring expansion/homologation--aldehyde condensation cascade using tert-trihalomethylcarbinols.

Falck J R JR He Anyu A Reddy L Manmohan LM Kundu Abhijit A Barma Deb K DK Bandyopadhyay A A Kamila Sukanta S Akella Radha R Bejot Romain R Mioskowski Charles C

Organic letters 20060901 20

Treatment of cyclic tert-trihalomethylcarbinols with CrCl(2) in THF/HMPA in the presence of aryl or aliphatic aldehydes initiates a cascade sequence of one carbon ring expansion-olefination affording conjugated exocyclic ketones. Acyclic tert-trihalomethylcarbinols undergo a comparable cascade of one carbon homologation-olefination. ...[more]

PMID: 16986971

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