Portal de Periódicos da CAPES

Facile Asymmetric Synthesis of Aziridine Derivatives via the Diastereoselective Reaction of Chiral Imines with Dimethylsulfonium Methylide

2002; Elsevier BV; Volume: 58; Issue: 1 Linguagem: Inglês

10.3987/com-02-s(m)32

1881-0942

Kimio Higashiyama, Masataka Matsumura, Ayako Shiogama, Takayasu Yamauchi, Sigeru Ohmiya,

Synthesis of β-Lactam Compounds

A simple method for the synthesis of chiral 2-substituted aziridine derivatives is described.The reaction pathway consists of the diastereoselective addition of dimethylsulfonium methylide to chiral imines derived from (R)-phenylglycinol and various aldehydes.Chiral aziridine derivatives are of interest not only for theoretical reasons but also because of their high reactivity arising from the release of strain energy inherent in a small ring.Use of reactive aziridine derivatives as intermediates in the asymmetric synthesis of several classes of compounds has been widely explored, 1 and many preparative methods have been developed for their synthesis. 2Among various synthetic methods for chiral aziridine derivatives, one of most promising is aziridination through the reaction of a chiral imine with a sulfur ylide 3 which involves stereocontrolled nucleophilic addition as the first step, followed by intramolecular nucleophilic substitution.However, the ylide methodologies can be applied only to an activated imine, that is, to the C=N double bonds with an N-electron withdrawing group such as p-tolylsulfonyl. 4This is a severe limitation of this methodology, especially because harsh conditions are generally required to cleave the strong sulfonamide bond.Despite recent advances, the tosyl group remains difficult to be removed from a sensitive substrate.