Anti-selective aldol reactions with titanium enolates of N-glycolyloxazolidinethiones.

نویسندگان

  • Michael T Crimmins
  • Patrick J McDougall
چکیده

[reaction: see text] A highly diastereoselective anti aldol addition utilizing a variety of N-glycolyloxazolidinethiones has been developed. Enolization of an N-glycolyloxazolidinethione with titanium (IV) chloride and (-)-sparteine followed by addition of an aldehyde activated with additional TiCl(4) resulted in highly anti-selective aldol additions, typically with no observable syn isomers. Allyl-protected glycolates demonstrated the highest levels of selection and yields, although O-benzyl and O-methyl glycolyloxazolidinethiones also performed well.

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عنوان ژورنال:
  • Organic letters

دوره 5 4  شماره 

صفحات  -

تاریخ انتشار 2003