Water-borne phosphine-functionalized core-cross-linked micelles (CCM) consisting of a hydrophobic core and a hydrophilic shell were obtained as stable latexes by reversible addition-fragmentation chain transfer (RAFT) in water in a one-pot, three-step process. Initial homogeneous aqueous-phase copolymerization of methacrylic acid (MAA) and poly(ethylene oxide) methyl ether methacrylate (PEOMA) is followed by copolymerization of styrene (S) and 4-diphenylphosphinostyrene (DPPS), yielding P(MAA-co-PEOMA)-b-P(S-co-DPPS) amphiphilic block copolymer micelles (M) by polymerization-induced self-assembly (PISA), and final micellar cross-linking with a mixture of S and diethylene glycol dimethacrylate. The CCM were characterized by dynamic light scattering and NMR spectroscopy to evaluate size, dispersity, stability, and the swelling ability of various organic substrates. Coordination of [Rh(acac)(CO)2 ] (acac=acetylacetonate) to the core-confined phosphine groups was rapid and quantitative. The CCM and M latexes were then used, in combination with [Rh(acac)(CO)2 ], to catalyze the aqueous biphasic hydroformylation of 1-octene, in which they showed high activity, recyclability, protection of the activated Rh center by the polymer scaffold, and low Rh leaching. The CCM latex gave slightly lower catalytic activity but significantly less Rh leaching than the M latex. A control experiment conducted in the presence of the sulfoxantphos ligand pointed to the action of the CCM as catalytic nanoreactors with substrate and product transport into and out of the polymer core, rather than as a surfactant in interfacial catalysis.

a b s t r a c tCore-cross-linked micelles (CCM) functionalized at the core with covalently linked bis(p-methoxyphenyl) phenylphosphine (BMOPPP) ligands have been synthesized by a three-step one-pot radical polymerization in emulsion, using the polymerization-induced self-assembly (PISA) strategy and reversible addition-fragmentation chain transfer (RAFT) as the controlling method. The CCM are obtained by chain extending in water poly(methacrylic acid-co-poly(ethylene oxide) methyl ether methacrylate) (P(MAAco-PEOMA), degree of polymerization of 30, MAA/PEOMA units molar ratio of 50:50) synthesized in a first step by RAFT with a 95:5 M mixture of styrene and 4-[bis(p-methoxyphenyl)phosphino]styrene (BMOPPS) units. The resulting micelles exhibiting a core composed of P(S-co-BMOPPS) segments with a degree of polymerization of 300 are then crosslinked in a third step with a mixture of di(ethylene glycol) dimethacrylate (DEGDMA) and styrene. The resulting BMOPPP@CCM exhibit a narrow size distribution (PDI ¼ 0.16) with an average diameter of 81 nm in water and swell in THF or by addition of toluene to the latex. The addition of [Rh(acac) (CO) 2 ] to the toluene-swollen latex results in metal coordination to the phosphine ligands. 31 P{ 1 H} NMR spectroscopy shows that the Rh centers undergo rapid intraparticle phosphine ligand exchange. Application of these nanoreactors to the aqueous biphasic hydroformylation of 1-octene shows excellent activity and moderate catalyst leaching.

We report the simple synthesis of tractable and high ion conducting PMMA-silica nanocomposites achieved by sol−gel processing. Mechanical strength was obtained by incorporating silica nanofillers covalently bonded to the polymer chains, whereas flexibility, thermal stability, and high ionic conduction were provided by the ionic liquid.

High catalytic activity (turnover frequencies up to 700 h À1) was achieved using new triphenylphosphinefunctionalized core cross-linked micelles, TPP@CCM, as nanoreactors and [Rh(acac)(CO) 2 ] as catalyst precursor for the aqueous biphasic hydroformylation of 1-octene. While the hydrophobic core of the polymer offers an adequate environment for the catalytic reaction, its hydrophilic shell confines the catalyst into the aqueous phase and prevents extensive leaching toward the substrate/product phase. Selectivity is better than that of the homogeneous reaction catalyzed by the Rh/PPh 3 system, with minor isomerization and linear to branched aldehyde ratios (l/b) between 3 and 6. Various operating parameters, such as catalyst/ligand concentration, temperature, and P/Rh ratio, were varied and proved that these nanoreactors do not suffer from significant mass transfer limitations. The effect of the nanoreactor hydrophobic core size and degree of functionalization on activity and on l/b regioselectivity has also been investigated. The possible causes of catalyst leaching are discussed.

Thermal decarbonylation of the acyl compounds [Mn(CO)5(CORF)] (RF = CF3, 1; CHF2, 2; CH2CF3, 3; CF2CH3, 4) yields the corresponding alkyl derivatives [Mn(CO)5(RF)] (RF = CF3, 5; CHF2, 6; CH2CF3, 7; CF2CH3, 8). Compounds 3, 4, 7 and 8 have not been previously reported. All compounds, except 8 which could not be obtained in a pure state, were fully characterized by analytical and spectroscopic methods, as well as by single-crystal X-ray diffraction for 1, 2, 4, 5, 6 and 7. The solution IR characterization in the CO stretching region, with the assistance of DFT calculations, has allowed the assignment of several weak bands to vibrations of the [Mn(12CO)4(eq-13CO)(RF)] and [Mn(12CO)4(ax-13CO)(RF)] isotopomers and a ranking of the RF donor power in the order CF3 < CHF2 < CH2CF3 ~ CF2CH3. The homolytic Mn-RF bond cleavage in [Mn(CO)5(RF)], carried out at various temperatures for compounds 5, 6 and 7 under saturation conditions, with trapping of the generated RF radicals by tris(trimethylsilyl)silane (TTMSS, 10 equiv), has yielded activation parameters ΔH‡ and ΔS‡ that are believed to represent close estimates of the homolytic bond dissociation thermodynamic parameters. The values (ΔH‡ = 53.8 ± 3.5 (5), 46.3±1.6 (6), 50.6±0.8 (7) kcal/mol; ΔS‡ = 66.0±9.5 (5), 55.8±4.7 (6), 65.4±2.2 (7) cal mol-1 K-1) are in close agreement with the results of a recent DFT study (J. Organomet. Chem. 2018, 864, 12-18).

A convenient route to organogels templated by high internal phase emulsions has been developed. Key is the use of a waterborne polymer latex loaded with a multiple hydrogen bond (MHB) functionality that becomes disentangled and transfers across the oil-water interface forming a gel network in the oil phase via hydrogen bond interactions.

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The phase diagram and microstructure of the ternary system ionic, liquid benzylpyridinium bis(trifluoromethanesulfonyl)imide)/nonionic surfactant (octylphenol ethoxylate)/toluene, were studied by using conductivity measurements, dynamic light scattering, pulse field gradient spin-echo NMR, and small-angle neutron scattering. Three microregions were identified by conductivity measurements according to the percolation theory. The sizes of IL-in-oil microemulsions with various IL fractions were then determined by NMR and DLS and were found to be in accordance with the radii of gyration (approximately 2 or 3 nm) determined by SANS. The reverse IL-in-oil microemulsions were used as nanoreactors to perform a Matsuda-Heck reaction between p-methoxyphenyl diazonium salt and 2,3-dihydrofurane in the presence of a palladium catalyst. The reaction yields obtained were greater in microemulsions (67%) than in bulk IL (33%), highlighting a strong effect of confinement. Moreover, a direct correlation between the quantity of IL and the reaction yield was observed.