Succinaldehyde 3-substituted esters

Mukaiyama et al. 200) synthesized optically active 3-substituted succinialdehyde acid esters (204) via a Michael-addition. The methyl ester of fumaraldehydic acid was converted into the corresponding aminal (203) by treatment with the (S)-proline-derived chiral diamine (99). The Michael-addition of Grignard reagent to the aminal, followed by hydrolysis produced stereoselectivily 3-substituted succinaldehydic acid ester (204) in good yield. 

Diastereoselective 1,4- (conjugate) additions of Grignard reagents to a chiral a,3-unsaturated aminals afford optically active 3-substituted succinaldehydic acid methyl esters with 85-93% ee (eq 4). ... 

Asymmetric Synthesis of 3-Substituted Succinaldehydic Acid Methyl Esters... 

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