Alkylidenemalonates, asymmetric

Table 5.10 Asymmetric conjugate addition of nitroalkanes to alkylidenemalonates under phase-transfer conditions.

Iron catalysts are very effective for the substitution of acyl chlorides [Eq. (198) 439.440] and thiol esters [Eq. (199) 376] with Grignard reagents to yield ketones. 1.4-Addition of Grignard reagents to an alkylidenemalonate derivative, as shown in Eq. (158) [182,183] was also promoted with an iron catalyst, but the degree of the asymmetric induction was inferior to that of the reaction catalyzed by nickel. 

P-Hydroxylamino esters. Alkylidenemalonic esters undergo Michael addition with the bissilylated hydroxylamine, while the corresponding acrylic esters react very sluggishly. The addition is subject to 1,2-asymmetric induction by an allylic substituent. 

Scheme 7.25 NHC-catalyzed asymmetric intermolecular Stetter reaction of glyoxamides with alkylidenemalonates reported by Rovis.

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