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The concept of fluorous biphasic separation has been applied in the recycling of rhodiumbased catalysts for the hydrosilylation of 1-alkenes and fluorinated 1-alkenes by following two approaches. Hydrosilylation of 1-hexene using various silanes and fluorous versions of) in fluorous biphasic solvent systems afforded the corresponding n-hexylsilanes in high yield. The catalyst activities were similar to those obtained using conventional [RhCl(PPh 3 ) 3 ]. The fluorous phase containing the catalyst was recycled at least twice without noticeable loss of activity, despite the fact that 12 and 1.7% of [Rh] was lost for 1 and 2, respectively, in the first cycle. The fluorous hydride intermediate) was identified by NMR spectroscopy. In a reverse approach, the original Wilkinson's catalyst was used for the hydrosilylation of 1H,1H,2H-perfluoro-1-alkenes in benzene or toluene as solvent. Fluorous extraction of the products enabled recycling of the nonfluorous catalyst.

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The universal model for predicting lipophilicity based on the mobile order and disorder (MOD) solution thermodynamics was used for the successful prediction of the partition coefficient of 88 fluorous and nonfluorous chemicals in fluorous biphasic PFMCH/toluene and FC-72/benzene binary solvent systems at 25 °C. A general thermodynamic expression aimed to calculate the distribution of substances in any fluorous biphasic system at any temperature is presented. Interestingly, the predictive expression requires the knowledge of only the molar volume and the nonspecific cohesion parameter of the solute allowing valuable estimation of log P of nonexisting fluorous molecules. The present partition model predicts that grafting more and/or longer perfluoroalkyl tails on a given substance does not automatically result in higher partition coefficients.

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A membrane reactor is presented for homogeneous catalysis in supercritical carbon dioxide with in situ catalyst separation. This concept offers the advantages of benign high-density gases, i.e., the possibility of achieving a high concentration of gaseous reactants in the same phase as the substrates and catalyst as well as easy catalyst localization by means of a membrane. For the separation of the homogeneous catalyst from the products an inorganic microporous membrane is used. The concept is demonstrated for the hydrogenation of 1-butene using a fluorous derivative of Wilkinson's catalyst [RhCl{P-(C 6 H 4 -p-SiMe 2 CH 2 CH 2 C 8 F 17 ) 3 } 3 ]. The size of Wilkinson's catalyst, 2-4 nm, is clearly larger than the pore diameter, 0.5-0.8 nm, of the silica membrane. The membrane will, therefore, retain the catalyst, while the substrates and products diffuse through the membrane. Stable operation and continuous production of n-butane has been achieved at a temperature of 353 K and a pressure of 20 MPa. A turnover number of 1.2 × 10 5 has been obtained during 32 h of reaction. The retention of the catalyst was checked using UV-vis spectroscopy and ICP-AAS; no rhodium or phosphorous species were detected at the permeate side of the membrane.

The effect of the nature of the anion on the performance of ionic rhodium catalysts has received little attention. Herein it is shown that the use of highly fluorous tetraphenylborate anions can enhance catalyst activity in both conventional and fluorous media. À (1 g)} the activity towards the hydrogenation of 1-octene in acetone increased in the order 1c < 1b < 1e < 1a < 1d~1f < 1g with 1g being twice as active as the commonly applied 1a. Despite the fluorophilic character introduced by the substituted tetraarylborate anions, the presence of some perfluoroalkyl-substituents in the cation was still required for achieving high partition coefficients. À (2g)} were prepared, which were active in the hydrogenation of 1-octene, 2g even more so than 3f. Both these highly fluorous catalysts could be recycled with 99% efficiency through fluorous biphasic separation, whereas the corresponding BF 4 À complex of 2g (2a) did not show any affinity for the fluorous phase.

The application of platinum(II) complexes based on the N,N-dimethylbenzylamine ligand (abbreviated as H-C,N) in macromolecular synthesis was demonstrated. Two cationic C,Nplatinum moieties were linked with a 4,4′-bipyridine bridge, giving [{C 6 H 4 (CH 2 NMe 2)-2-Pt-(PPh 3)} 2 (4,4′-bpy)](BF 4) 2 (2), the crystal structure of which was determined. To introduce C 60 groups into this assembly, [1,2]-methanofullerene-substituted H-C,N ligands were prepared and platinated using cis-PtCl 2 (DMSO) 2. Application of the methanofullerene C,Nplatinum complexes in the preparation of macrostructures afforded insoluble compounds. Therefore, phosphine ligands containing perfluoroalkyl groups were introduced into the fullerene-based complexes via a ligand exchange reaction. These fluorous complexes showed enhanced solubility in organic and fluorinated solvents. A soluble bismethanofullerene C,Nplatinum(II) structure with a 4,4′-bipyridine bridge was obtained using these fluorinated fullerenes.