Nucleophilic phosphanylation of orf/zo-fluorophenylacetic acid or orf/jofluorobenzylamine with PhPH2 using KOfBu as the base affords the hydrophilic tertiary phosphanes 3 and 4a with terminal CH2-COOH and CH2-NH2 substituents. The corresponding secondary phosphane li gands 2 or 5 may be obtained by Pd-catalyzed P-C coupling of orr/20-iodophenylacetic acid with PhPH2 or selective nucleophilic phosphanylation of orf/jo-fluorophenylacetic acid. Novel phosphonatomethyl derivatives 7a, 7b of triphenylphosphane have been obtained in a two sta ge synthesis using orf/zo-iodobenzylchloride or w^ta-iodobenzylbromide as starting materials. Arbusov reaction with P(OEt)3 and Pd-catalyzed P-C coupling reactions with Ph2PH gave the esters 7a, 7b. Purification of 7a was achieved via its BH3 adduct 8a. Deprotection, hydrolysis and neutralisation with NaOH affords the water soluble sodium salts 9a,9b. a-Hydroxy and a-benzylamino derivatives 12 and 14 of orr/zo-diphenylphosphanobenzyl phosphonate (e.g. 7a) and the corresponding Me2P (0) analogs 13 and 16 are accessible in a straightforward man ner by addition of (M e0)2P(0)H or Me2P(0)H to orf/?o-phosphanobenzaldehyde 11a or its benzaldimino derivative 15, respectively. An improved synthesis for lla -llc has been develo ped. Reaction of 11a with the Wittig reagent Ph3P=C(H)COOEt and subsequent hydrolysis of the intermediate ester 17a affords o/t/?o-diphenylphosphano cinnamic acid 17. The catalytical activity of 1,9a, 9b and related ligands in Suzuki-type coupling reactions has been investigated. Derivate des Triphenylphosphans mit COOHund P (0 )(0 R )2-Gruppen (z.B. A [2], B [3]) sind als Katalysatorliganden für die Hydrofor mylierung und Oligomerisation von Olefinen [4] sowie die Carbonylierung von Benzylhalogeni den in Zweiphasensystemen [3] von Bedeutung. Durch Immobilisierung aromatischer Phosphane mit P (0 )(0 R )2-Resten (B) an anorganischen Ma terialien (Zirconium(IV)-phosphat, -phosphonat, -phosphit) wurden geträgerte Katalysatoren erhal ten, die für Hydroformylierungs-und Heck-Reaktionen in heterogenen Systemen mit Erfolg einge setzt wurden [5, 6]. Die Einschiebung einer CH(Z)-Brücke in A und B führt zu Liganden C bzw. D mit flexibler