Sulfinimines, chiral asymmetric synthesis

Thiosulfinate 129 has been used for the synthesis of various chiral sulfinyl derivatives such as sulfoxides, sulfmamides, and sulfinimines in good yield, tert-Butanesulfinyl ketimines have been successfully used for the asymmetric synthesis of a,a-dibranched aminesI09h as well as for the synthesis of o.p. amino acids.109 ... 

Kim, D.Y., Suh, K.H., Choi, J.S., Mang, J.Y, and Chang, S.K., Asymmetric synthesis of aziridinyl phosphonates using Darzens-type reaction of chloromethyl phosphonate to chiral sulfinimines, Synth. Commun., 30, 87, 2000. 

Enantiopure sulfinimines are ammonia imine synthons useful in the asymmetric synthesis of amines and -amino acid derivatives. Sulfinimines unavailable via the Andersen synthesis (R = H) are prepared hy asymmetric oxidation of the sulfenimines, ArS-N=C(R)PhX, with (+)-( ) or (-)-(1) at -20 to 20 °C in CCI4 (eq 8). Crystallization improves the ee to >95%. The sulfoxide chiral recognition model correctly predicts the configuration of the product. 

Cyclic (hetero- and carbocyclic) vinyl sulfoxides have been prepared by a tandem Michael addition/Homer olefination reaction of a-phosphorylvinyl sulfoxides and carbonyl compounds bearing a nucleophilic center. Using optically active a-phosphorylvinyl sulfoxides a series of enantiomeric cyclic vinyl sulfoxides in which the chiral sulfinyl group is bonded to a chromene, pyrrazolyne, quinoline or cyclopen-tene ring, has been obtained. The H-W-E reaction of aldehydes with sulfinimine-derived 3-oxo pyrrolidine phosphonates (228) represents a new method for the asymmetric synthesis of ring-functionalized cw-2,5-disubstituted 3-oxo pyrrolidines (229) (Scheme 90). ... 

New asymmetric synthesis of the indolizidine alkaloids (-l-)-monomorine I (673) and (—)-indolizidine 195B (674) has been achieved from sulfinimine-derived chiral building blocks N-sulfinyl-5-amino-p-ketophosphonate (671) via 3-oxopyrrolidine phosphonates (672) (Scheme 169). ... 

The first section of this chapter describes the preparation and several synthetic applications of a-fluoroalkyl P-sulfmyl enamines and imines the second deals with the chemistry of di- and trifluoropyruvaldehyde A, 5-ketals, stereochemically stable synthetic equivalents of P-di and P-trifluoro a-amino aldehydes, which can be prepared from the corresponding p-sulfinyl enamines the third overviews the preparation of chiral sulfinimines of trifluoropyruvate and their use to prepare a library of a-trifluoromethyl (Tfm) a-amino acids the fourth section is mainly dedicated to the asymmetric synthesis of monofluorinated amino compounds, using a miscellany of methods such as MifstmobuAike azidation of P-hydroxy sulfoxides, ring opening of fluoroalkyl epoxides with nitrogen-centered nucleophiles and 1,3-dipolar cycloadditions with chiral fluorinated dipolarophiles. 

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