N-alkoxyacrylamides as substrates for enantioselective Diels-Alder reactions.
[reaction: see text] The use of N-alkoxyacrylamides as substrates for Lewis acid catalyzed Diels-Alder reactions has been examined. Enantioselectivities up to 92% ee have been achieved using very simple chiral Lewis acids prepared from triisobutylaluminum and 2,2-dimethyl-alpha,alpha,alpha',alpha'-tetra-1-naphthalenyl-TADDOL (1-NaphtTADDOL). The use of Yamamoto's Zn-BINOL, easily prepared from Et2Zn and 1,1'-bi-2-naphthol (BINOL), proved to be even more efficient, and enantioselectivities up to 96% ee were achieved.
Corminboeuf
Olivier
O
Department of Chemistry and Biochemistry, University of Berne, CH-3000 Berne 9, Switzerland.
Renaud
Philippe
P