PREPARATION, REACTIONS AND CATALYTIC ACTIVITIES OF WATER-SOLUBLE IRIDIUM-SULFONATED TRIPHENYLPHOSPHINE COMPLEX

Water soluble iridium complex, IrCl(CO)(TPPTS)(2) . xH(2)O (1) (TPPTS= m-trisulfonated triphenylphosphine) has been prepared from the reactio n of a water soluble complex, IrCl(COD)(TPPTS)(2) . 6H(2)O (COD=1,5-cy clooctadiene) with CO and unambiguously characterized by electronic ab sorption, P-31 NMR, C-13 NMR and IR spectral data. Complex 1 catalyzes the hydration of terminal alkynes to give ketones in aqueous solution s at room temperature. The rate of PhC=CK hydration dramatically incre ases with addition of MeOH to the reaction mixture in H2O, which is un derstood in terms of i) the excellent miscibility between H2O and MeOH and ii) the assumed catalytic hydration pathway involving the initial formation of (alkyne)IrCl(CO)(TPPTS)(2).