Schrader, Thomas; Kirsten, Christian; Herm, Michael:
Chelate complexes with the P:O-double bond - a new concept for asymmetric synthesis.
1999
In: Phosphorus, Sulfur and Silicon and the Related Elements, Band 144-146 (1999), S. 161 - 164
Artikel/Aufsatz in Zeitschrift / Fach: Chemie
Titel:
Chelate complexes with the P:O-double bond - a new concept for asymmetric synthesis.
Autor(in):
Schrader, Thomas im Online-Personal- und -Vorlesungsverzeichnis LSF anzeigen; Kirsten, Christian; Herm, Michael
Erscheinungsjahr:
1999
Erschienen in:
Phosphorus, Sulfur and Silicon and the Related Elements, Band 144-146 (1999), S. 161 - 164
ISSN:

Abstract:

A new strategy for asym. synthesis uses highly efficient cyclic P amidate auxiliaries capable of forming a rigid chelate complex with a metal enolate. The authors' research on asym. synthesis of ketone cyanohydrins is reviewed. Newly reported is the Pd(II)-catalyzed highly stereospecific rearrangement of olefinic cyanohydrin phosphates (e.g. 2-Ph-3-Me-3-Me-2-O-2-MeCH:CHCH(R)(CN)O-1,3,2-oxazaphospholidine) to phosphate protected g-hydroxy methacrylic nitriles (e.g. 2-Ph-3-Me-3-Me-2-O-2-NCC(R):CHCHMeO-1,3,2-oxazaphospholidine). Also, initial attempts at asym. N-methyl-a-amino acid synthesis are reported. For example, a high chem. yield of I with a de of 92% was obtained, but it was not possible to use higher homologous alkyl halides to alkylate alpha to the carbonyl C.