Stereoselective Synthesis of P-Stereogenic Aminophosphines: Ring Opening of Bulky Oxazaphospholidines
摘要:
A highly diastereoselective and efficient synthesis of P-stereogenic bulky alkyl and aryl aminophosphines that relies on ring opening of tert-butyl-oxazaphospholidine 2 is described. Ring opening with several organometallic reagents takes place with inversion of configuration at the phosphorus center as it has been demonstrated by X-ray analysis of two ring-opened intermediates. The unprecedented reactivity observed is attributed to the presence of a free NH functionality that facilitates the attack of the organometallic reagent in an S(N)2@P-type process.
Set the N free! The reactivity of the amino group of P‐stereogenic aminophosphines allows the further elaboration of the aminophosphine unit whilst preserving the original chirality of the phosphorus atom (see picture; Rh green). P‐stereogenic aminodiphosphine ligands can easily be prepared in optically pure forms, feature distinct structural and electronic characteristics, and can be used in asymmetric
[EN] ENANTIOMERICALLY ENRICHED AMINODIPHOSPHINES AS LIGANDS FOR THE PREPARATION OF CATALYSTS FOR ASYMMETRIC SYNTHESIS<br/>[FR] AMINODIPHOSPHINES ÉNANTIOMÉRIQUEMENT ENRICHIES COMME LIGANDS POUR LA PRÉPARATION DE CATALYSEURS POUR UNE SYNTHÈSE ASYMÉTRIQUE
申请人:ENANTIA S L
公开号:WO2011098160A1
公开(公告)日:2011-08-18
The present invention relates to enantiomerically enriched aminodiphosphine ligands where the chirality is located in the phosphorus atom and their preparation process, to catalysts containing them and their preparation process, as well as their use in asymmetric synthesis.
Enantiomerically Enriched Aminodiphosphines as Ligands for the Preparation of Catalysts for Asymmetric Synthesis
申请人:Alonso Xalma Mónica
公开号:US20120309997A1
公开(公告)日:2012-12-06
The present invention relates to enantiomerically enriched aminodiphosphine ligands where the chirality is located in the phosphorus atom and their preparation process, to catalysts containing them and their preparation process, as well as their use in asymmetric synthesis.
The synthesis of P-stereogenic aminophosphine-boranes has been developed on the basis of umpolung reactivity of in situ generated alkylarylphosphido-boranes, which are normally configurationally unstable intermediates. In our case, their high configurationalstability was due to the slow release of the hydroxyalkyl protecting group, together with the fast formation of the iodophosphanylborane in the