149. Sultam-directed asymmetric syntheses of α-amino acids
     Oppolzer, W.
     in Chirality in Drug Design and Synthesis; Brown, C. (Ed.) Academic Press: London, 1990; Chap. 11; p. 199-214

Enantiomerically pure α-amino acids are of immense interest not only per se, but also as chiral building blocks and as starting materials for chiral reagents and catalysts. This chapter describes practical routes to this class of compounds via π-face-selective formation of either the C_α-R or C_α-NH₂ bond. Convenient sources of chirality are bornane-10,2-sultam, (-)-2 and its antipode (+)-2, accessible from inexpensive (+)- and (-)-camphorsulfonic acids in two simple operations. Both chirophore enantiomers are commercially available in kg-quantities. Addition reactions to N-enoyl derivatives (I), and reactions of enolates (II) with electrophiles, proceed in high yield and with good to excellent π-face discrimination. The chapter also describes that compared to a plethora of auxiliaries so far developed for asymmetric synthesis, sultams are among the most practical and universal.

DOI : 10.1016/B978-0-12-136670-4.50017-5 

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