Theoretical Evidence of Pyramidalized Bicyclic Serine Enolates in Highly Diastereoselective Alkylations

  1. Aydillo, C. 1
  2. Jiménez-Osés, G. 1
  3. Busto, J.H. 1
  4. Peregrina, J.M. 1
  5. Zurbano, M.M. 1
  6. Avenoza, A. 1
  1. 1 Universidad de La Rioja
    info

    Universidad de La Rioja

    Logroño, España

    ROR https://ror.org/0553yr311

Revista:
Chemistry - A European Journal

ISSN: 0947-6539

Ano de publicación: 2007

Volume: 13

Número: 17

Páxinas: 4840-4848

Tipo: Artigo

DOI: 10.1002/CHEM.200601746 PMID: 17366514 SCOPUS: 2-s2.0-34250318626 WoS: WOS:000247219900016 GOOGLE SCHOLAR

Outras publicacións en: Chemistry - A European Journal

Resumo

A new chiral serine equivalent and its enantiomer have been synthesized from (S)- and (R)-N-Bocserine methyl esters (Boc: tert-butyloxy-carbonyl). The use of these compounds as chiral building blocks has been demonstrated in the synthesis of α-alkyl α-amino acids by diastereoselective po tassium enolate alkylation reactions and subsequent acid hydrolyses. Theoretical studies were performed to eluci date the stereochemical outcome of both the formation of five-membered cyclic N,O-acetals and the subsequent alkylation process, which occurs with total retention of configuration. This feature could be explained in terms of the high degree of pyramidalization of enolate intermediates. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.