Compounds Derived from Aminoacetic Acid

Compounds Derived from Substituted Aminoacetic Acids... 

Compounds Derived from Substituted Aminoacetic Acids [5958] p. 1298... 

Palladium-catalysed asymmetrie allylations of various carbonyl compounds have been studied by Hiroi et al. using various types of chiral sulfonamides derived from a-amino acids. In particular, the chiral bidentate phosphinyl sulfonamide derived from (5)-proline and depicted in Scheme 1.63 was employed in the presence of palladium to eatalyse the allylation of methyl aminoacetate diphenyl ketimine with allyl aeetate, leading to the eorresponding (7 )-product with a moderate enantioseleetivity of 62% ee. This ligand was also applied to the allylation of a series of other nueleophiles, as shown in Seheme 1.63, providing the eorresponding allylated produets in moderate enantioseleetivities. 

The aromatic ring system has been prepared both from quinoxaline intermediates and from 1-phenylimidazoles. Reaction of the 2-chloroquinoxalines 1 with aminoacetaldehyde dimethylacetal followed by acid treatment of the resultant aminoacetals gave imidazo[l,2-ajquinoxaline (2) and its 4-phenyl derivative (3). Compound 3 was the... 

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