New (alpha-Hydroxyalkyl)phosphorus Amphiphiles: Synthesis and Dissociation Constants.
Direct synthesis of free (alpha-hydroxyalkyl)phosphinic acid amphiphiles 1 can be readily realized by sonication of the heterogeneous mixture of 50% aqueous hypophosphorous acid and long-chain aldehydes in the presence of catalytic amounts of hydrochloric acid. Oxidation of these phosphinic acids by DMSO in the presence of catalytic amounts of iodine quantitatively leads to the corresponding phosphonic acids 3. IR spectra of the phosphinic acids 1 in the condensed phase and in solution reveal the presence of intra- and intermolecular associations. Dissociation constants of the phosphorus acids 1 and 3 determined by potentiometric and (31)P NMR titrations show a good correlation between the two methods. The phosphinic acid amphiphiles 1 are slightly stronger than the corresponding phosphonic acids 3. (alpha-Hydroxyalkyl)phosphonium chlorides are prepared in good yields from the phosphine PH(3) and long-chain aldehydes in acidic media.
Albouy
Dominique
D
Laboratoire des IMRCP (UMR 5623) and Fédération de Recherche FR 14, Université Paul Sabatier, 118 route de Narbonne, Bât. 2R1, 31062 Toulouse Cedex 04, France.
Brun
Alice
A
Munoz
Aurelio
A
Etemad-Moghadam
Guita
G