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Tripod Rhodium COD Complexes: Synthesis, Structure, Dynamics and Catalysis The reaction of the tripod ligands R′C(CH2PR2)3 (1a–c) and X2POCH[CH2P(Ph)2]2 (2a–c) with [RhI(COD)Cl]2] is investigated. It yields tripod rhodium COD complexes [(1a–c)RhI(COD)]Y (3a–c) and [(2a–c)RhI(COD)]Y [4a–c; Y = B(Ph)4, PF6]. The tripod ligand is coordinated by all three donor groups in each case, irrespective of the different donor capabilities of the coordinating groups. The solid state structure of compounds 3a–c and 4a is determined by X‐ray analysis. The observed coordination polyhedra delineate the variation from the idealized trigonal bipyramide to an idealized quadratic pyramide. In solution the analysis of the NMR spectra shows a rapid intramolecular interconversion according to a turnstile pseudo rotation. The complexes 3a and 4a are found to be catalysts for the hydrogenation of prochiral olefines.

Chiral Tripodal Ligands Bearing a Phosphite Donor Group: Synthesis and Coordination Chemistry The mechanism of the reaction of epichlorohydrine (H–CH2Cl) (1) with lithium phosphides is analysed. A neighbouring‐group mechanism has been found to be the essential driving force in this reaction. Monophosphanyl alcohols such as HOCH(CH2P(Ph)2)(CH2Cl) (2) and epoxides (Ph)2PCH2– (3) are characterized as intermediates. The mechanism leads to a rapid one‐pot method for the synthesis of chiral racemic as well as enantiomerically pure bis(phosphanyl) alcohols HOCH(CH2PR2)(CH2PR 2′) (4). The resulting bis(phosphanyl) alcohols 4 react easily with X2PCl (X = Cl; Ph; or X2 = 1,2‐ethanedioxy‐2,2′‐biphenyldiyldioxy‐) to yield the mixed donor group tripodal ligands X2POCH(CH2PR2)(CH2PR′2) (5, 6) containing both phosphite, phosphinite or phosphorodichloridite and phosphane donor groups. The identity of these compounds were proved by 1H‐, 31P‐ and 13C‐NMR spectroscopy, mass spectra, microanalysis as well as X‐ray analysis. The coordination capabilities of these novel ligands are demonstrated by the synthesis and characterization of a (cyclooctadiene)rhodium complex {[(5c)Rh(I)COD]PF6} (7) of the ligand 5c, exhibiting the typical hetero‐bicyclooctane tripod metal cage of this type of tripod complexes.

Tripod‐Cobalt Formate Complexes of Oxidation States +II and +I The syntheses of the (tripod)cobalt formate complexes [(tri‐pod)Co(O2CH)]n+ (1/1+; n = 0, 1; tripod = CH3C(CH2PPh2)3) are presented. The structures are established by X‐ray analyses as well as the usual analytical techniques.