2003 Aminocarboxylic acids (hydrazinocarboxylic acids) and esters

200348.fm Page 72 Friday, October 31, 2003 2:17 PM

Aminocarboxylic acids (hydrazinocarboxylic acids) and estersP 0270 Diastereoselective Intermolecular Addition of the 1,3-Dioxolanyl Radical to

N-Acyl Aldohydrazones. Asymmetric Synthesis of α-Amino Acid Derivatives. — N-Acyl aldohydrazones efficiently trap the 1,3-dioxolanyl radical without external ac-tivation at temperatures as low as -78 °C. The process can be efficiently carried out as a one-pot procedure starting from aldehydes and leads to (IV) in good yields and high stereoselectivities (for the alkyl derivatives). The method is used as key step for the asymmetric synthesis of α-amino acid (V). — (FERNANDEZ, M.; ALONSO*, R.; Org. Lett. 5 (2003) 14, 2461-2464; Dep. Quim. Org., Fac. Farm., Univ. Santiago de Compostela, E-15782 Santiago de Compostela, Spain; Eng.) — Steudel

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