Glyoxylate derived aldimine

Whiting et al. [20] found the catalytic system for an aza Diels-Alder reaction by the use of a combinatorial approach to catalyst selection. When methyl glyoxylate-derived aldimine 25 was reacted with Danishefsky s diene 24 in the presence of the chiral magnesium catalyst (10 mol %), prepared in-situ from chiral diphenylethylenediamine 23, Mgl2, and 2,6-lutidine, the Diels-Alder product 26 was obtained in 64 % yield with 97 % ee (Sch. 9). 

Some bifunctional 6 -OH Cinchona alkaloid derivatives catalyse the enantioselective hydroxyalkylation of indoles by aldehydes and a-keto esters.44 Indole, for example, can react with ethyl glyoxylate to give mainly (39) in 93% ee. The enan- tioselective reaction of indoles with iV-sulfonyl aldimines [e.g. (40)] is catalysed by the Cu(OTf)2 complex of (S)-benzylbisoxazoline (37b) to form 3-indolylmethanamine derivatives, in up to 96% ee [e.g. (41a)] 45 Some 9-thiourea Cinchona alkaloids have been found to catalyse the formation of 3-indolylmethanamines [e.g. (41b)] from indoles and /V-PhS02-phenyli mines in 90% ee.46 Aryl- and alkyl-imines also give enantioselective reactions. 

Table 9 1,3-Asymmetric Induction in the Addition of Allyl Organometallic Reagents (37) to Glyoxylate Aldimines (36) Derived from Chiral Amines (Equation 9) - ...

A-Sulfonylaldimines produced by condensation of SES-NFI2 with various aldehydes are converted into enantiomerically enriched aziridines upon reaction with certain sulfur ylides. The same types of aldimines undergo [3 4- 2] cycloaddition reactions with 2,3-butadienoates in the presence of triphenylphosphine to give 2,5-dihydrop3TToles, while that derived from SES-NSO and ethyl glyoxylate reacts efficiently with chiral sulfonimidoyl substituted bis(allyl)titaniumcorr5)lexes to give /3-alkyl-)/,5-unsaturated a-amino acid derivatives. ... 

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