Sodium in liquid ammonia—a versatile tool in modifications of arylphosphine oxides
作者:Marek Stankevič、Adam Włodarczyk、Magdalena Jaklińska、Renata Parcheta、K. Michał Pietrusiewicz
DOI:10.1016/j.tet.2011.09.045
日期:2011.11
modifications of tertiary arylphosphine oxides based on their reaction with sodium in liquid ammonia is presented. Depending on the structure of the starting compounds, either dearomatisation of the phenyl substituent or cleavage of a P-aryl bond from phosphorus atom can be selectively performed and the corresponding (1,4-cyclohexadien-3-yl)phosphine oxides or secondary phosphine oxides were obtained
A process for the preparation of 3-(3,4-dihydroxyphenyl)-L-alanine (L-DOPA) wherein .alpha.-acetamido-4-hydroxy-3-alkoxy-cinnamic acid acetate is subjected to catalytic asymmetric hydrogenation to yield an optically active mixture N-acetyl-3-(4-hydroxy-3-alkoxyphenyl)-alanine acetate, with the L enantiomorph being present in a major amount and the D enantiomorph being present in a minor amount, from which N-acetyl-3-(4-hydroxy-3-alkoxyphenyl)-L-alanine acetate can be easily recovered and is then converted to L-DOPA. Novel precursors for L-DOPA are prepared in the process of this invention.
[EN] PROCESSES FOR THE STEREOSELECTIVE PREPARATION OF P-CHIRAL FOUR -COORDINATED PHOSPHORUS BORANE COMPOUNDS AND P-CHIRAL THREE-COORDINATED PHOSPHORUS COMPOUNDS<br/>[FR] PROCÉDÉS POUR LA PRÉPARATION STÉRÉOSÉLECTIVE DE COMPOSÉS DE BORANE DE PHOSPHORE À QUATRE COORDINATIONS P-CHIRAUX ET DE COMPOSÉS PHOSPHORÉS À TROIS COORDINATIONS P CHIRAUX
申请人:UNIV DUBLIN
公开号:WO2012113889A1
公开(公告)日:2012-08-30
Processes for the stereoselective preparation of P-chiral four-coordinated phosphorus borane compounds and P-chiral three-coordinated phosphorus compounds.
A process for the stereoselective preparation of a P-chiral four-co-ordinated phosphorus compound, the process comprising reacting a first reactant selected from the group consisting of a chiral alcohol, chiral amine or chiral thiol, with a second reactant comprising a P-chiral three-co-ordinated phosphorus compound, in the presence of an electrophile.
A process for the stereoselective preparation of a P-chiral four-co-ordinated phosphorus compound, the process comprising reacting a first reactant selected from the group consisting of a chiral alcohol, chiral amine or chiral thiol, with a second reactant comprising a P-chiral three-co-ordinated phosphorus compound, in the presence of an electrophile.