Nucleophilic Carbenes as Organocatalysts
165
Scheme 6. Initial screening of different azolium salts
Scheme 7. A certain steric demand of the NHC seems to be key to success
aldehydes could be used and resulted in yields of γ-lactone products
ranging from 30% to 70% with generally hardly any benzoin or Stetter product being produced. It should be noted that using a 2:1 or a 1:2
165
Scheme 6. Initial screening of different azolium salts
Scheme 7. A certain steric demand of the NHC seems to be key to success
aldehydes could be used and resulted in yields of γ-lactone products
ranging from 30% to 70% with generally hardly any benzoin or Stetter product being produced. It should be noted that using a 2:1 or a 1:2