Synthesis and Alkali-Metal-Ion Complexation of P-Stereogenic Diphosphacrowns.

ABSTRACT: Phosphine is conformationally stable because of the high inversion energy barrier of the phosphorus atom, which allows the phosphorus atom to become a chiral center. Thus, enantiopure P-stereogenic 12-, 15-, 18-, and 21-membered aliphatic phosphines "diphosphacrowns" were synthesized from secondary P-stereogenic bisphosphine as a chiral building block. Their complexation behaviors with alkali metal ions are investigated in comparison with benzo-18-diphosphacrown-6 and benzo-18-crown-6. 15-, 18-, and 21-Membered diphosphacrowns captured alkali metal ions to form 1:1 metal complexes. Unique guest selectivity was observed, as diphosphacrowns encapsulated smaller alkali metal ions than common crown ethers; for example, 18-membered diphosphacrowns interacted more strongly with Na(+) than K(+).

SUBMITTER: Morisaki Y 

PROVIDER: S-EPMC4981053 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature