Enantioenriched acid, ester, and ketone β-phenyl homoenolate synthetic equivalents from N-Boc-N-(p-methoxyphenyl)cinnamylamine

✍ Scribed by Marna C Whisler; Eric D Soli; Peter Beak

• Book ID: 104211212
• Publisher: Elsevier Science
• Year: 2000
• Tongue: French
• Weight: 64 KB
• Volume: 41
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)01663-4

✦ Synopsis

Oxidation of the b-substituted highly enantioenriched aldehydes obtained by hydrolysis of the 3,3-disubstituted enecarbamates affords enantioenriched b-substituted acids and esters. Lithiation of enantioenriched 3,3-disubstituted enecarbamates and subsequent reaction with electrophiles provides vinylically substituted enecarbamates. The use of benzyl and alkyl halide electrophiles affords a-substituted enecarbamates, which can be hydrolyzed to provide enantioenriched b-substituted ketones. Reaction of the lithiated intermediate with ketones affords oxazolidinones, which can be reductively ring-opened with DIBAL and hydrolyzed to provide enantioenriched b-substituted, a%-hydroxy ketones. These transformations demonstrate that the enantioselective lithiation of N-Boc-N-(p-methoxyphenyl)cinnamylamine provides a reactive intermediate which can be a ketone, acid, or ester homoenolate synthon.