Enantioselective oxidation of thioethers: synthesis of trans-2-N,N-dialkylacetamide-1,3-dithiolanes-S-oxide and their use in asymmetric aldol-type reactions
作者:Martina Corich、Fulvio Di Furia、Giulia Licini、Giorgio Modena
DOI:10.1016/s0040-4039(00)79595-5
日期:1992.5
(−)-trans-2-N,N-dialkylacetamide-1,3-dithiolanes-S-oxide 2 have been obtained in high d.e. (>99:1) and e.e. (up to 94%), >98% after crystallization) by enantioselective oxidation [Ti(i-PrO)4, (+)-DET, t-BuOOH]. The aldol-type addition of the magnesium enolate of the N,N-diethyl derivative (−)-2b to iso-butyraldehyde afforded good chemical yields of a single diastereomer.
(-)-反式-2- N,N-二烷基乙酰胺-1,3-二硫杂环戊烷-S-氧化物2以高de(> 99:1)和ee(最高94%)获得,结晶后> 98% )通过对映选择性氧化[Ti(i- PrO)4,(+)-DET,t -BuOOH]。N,N-二乙基衍生物(-)- 2b的烯醇镁的醛醇型加成到异丁醛中可得到单一非对映异构体的良好化学收率。