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1 2009

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Asymetryczna synteza α, β-diaminokwasów

Błaszczyk R., Gajda T.

Wiadomości Chemiczne

2009

[Z] 63, 7-8

635-684

Through the years, α,β-diamino ac6ds and their derivatives have attracted a great deal of attention among organic chemists because of their biological significance [1, 2]. This review deals with the synthetic approaches of α,β-diamino acids and their derivatives (e.g., esters, amides) using asymmetric synthesis methods described in the literature up to the end of 2008. Aziridines and 3-amino-β-lactams are beyond the scope of this review and will be only considered as intermediates in the synthesis of acyclic derivatives. The methods found in the literature can be classified essentially in two main categories: methods that require a new carbon-carbon single bond construction and method based on the functional groups transformation reactions within the carboxylic acids skeleton. A great number of C-C forming methods are the addition reactions of glycine derivatives or nitro compounds to imines (Mannich-type reactions). The asymmetric induction requires chiral substrate usage (e.g., chiral sulfinimines, chiral glycinates) [30-37, 61-67] or results from the application of chiral catalysts (e.g., chiral Lewis acids, chiral PTC catalysts and other organocatalysts) [39-48, 50-60] . Strecker's reaction using chiral imines or related compounds is also often used [69-77]. Methods begining from the existing carbon skeleton and based on the modification of the functional groups are as follows: catalytic asymmetric diamination and aminohydroxylation of α,β-unsaturated carboxylic esters [92-100, 107-109]. Subsequent transformation of the hydroxy group into the amine group in the hydroxyamino acids derivatives is then necessary [100-109]. The direct introduction of the amino moiety into the β-amino esters via electrofilic amination is also described [120-131]. The title compounds can also be obtained by catalytic enantioselective reduction of dehydrodiamino acids derivatives[117-119].