The Synthesis of a Chiral Hexaphenyl-18-crown-6 Derivative

All articles of this category The stereospecific synthesis of (2 R ,3 R ,8 R ,9 R ,14 R ,15 R )-2, 3,8,9,14,15-hexaphenyl-1,4,7,10,13,16-hexaoxacyclooctadedecane [( R,R,R,R,R,R )- 12 ] from ( R,R )-hydrobenzoin [( R,R )- 1 ] is reported. The ability of ( R,R,R,R,R,R )- 12 to act as a chiral solid-liquid phase-transfer catalyst in an asymmetric Michael addition is compared with the efficiencies of other chiral di- and tetra-substituted 18-crown-6 derivatives, both with respect to product conversions and chirality transfers from catalysts to products.