• It could be proved that ketone 1, which is derived from binaphthalene really is a good catalyst for epoxidation and that it gives a high enantiomeric excess.
  
• The mannitol-derivative 2 was supposed to be a good catalyst also. The large adamantyl-groups should have enhanced the effect of the chiral centers and thereby rise the enantiomeric excess. Yet, this synthesis failed.
  

Synthesis of the catalyst 1:

• Bromine-Addition to 2-methylnaphthalene in postion 1.
  
• Oxidation of the methyl-group to the carbon acid.
  
• Synthesis of the methylester via thes acid chlorid.
  
• Ullmann-coupling to the binaphthyl-derivative.
  
• Acetic working-up gives the free acid.
  
• Separation of the enantiomers with Brucin
  
• Formation of the ester with 1,3-dihydroxyacetone
  

Þ in situ epoxidation of trans-stilbene: Yield 70 %, ee = 44 %.

Ketone 1

The second aim of this project was the synthesis of the C2-symmetric, chiral catalyst 2 on a D-mannitol basis. I did not succeed in acetalizing in the 1,2- and 5,6-position, but I could obtain the triacetalised product. Even the other pathway (forming the ether first) did not lead to the desired product.

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