ChemInform Abstract: Models for the Use of α‐Amino Acids as Chiral Auxiliaries in Asymmetric Diels‐Alder Reactions.

Abstract

1992 cycloaddition reactions cycloaddition reactions O 0070 -089Models for the Use of α-Amino Acids as Chiral Auxiliaries in Asymmetric Diels-Alder Reactions.-Chiral N-acryloyl derivatives of α-amino acids such as the prolinate (II) undergo asymmetric Diels-Alder reactions with cyclopentadiene (I) to produce predominantly the endo-adducts (±)-( III). This result is explained by the formation of a complex between the dienophile and TiCl4 bearing the acryloyl moiety in syn conformation and by the attack of the diene at the Si face. -(BUENO, M. P.; CATIVIELA, C. A.; MAYORAL, J. A.; AVENOZA, A.; J. Org. Chem. 56 (1991) 23, 6551-6555; Dep. Quim. Org., Inst. Cienc. Mat. Aragon, Univ., CSIC, 50009 Zaragoza, Spain; EN)