Magnetic nanoparticles(MNP) functionalized by a new bis(diphenylphosphinomethyl)dopamine(bpd) of type MNP@bpd were prepared, characterized and their reusability as catalysts were assessed by hydroformylation reaction.A new bis(diphenylphosphinomethyl) dopamine (bpd) ligand has been prepared and anchored on the surface of magnetic nanoparticles (MNPs). The obtained ligand and the surface functionalized nanoparticles of type MNP@bpd have been characterized by various analytical techniques, such as NMR, IR, TEM, XRD, and VSM. TEM shows homogeneous distribution of the particles with the size ranging 5-7 nm. XRD Rietveld analysis confirm the formation of pure and single Fe 3 O 4 phase with high crystallinity. The ligands anchoring on the magnetic nanoparticles surface have been confirmed by the shift of the characteristic Fe-O vibration band in the FT-IR spectrum, and has been supported by the stepwise weight loss in TGA as a function of temperature. The phosphorus content determined by ICP-MS is approximately 0.39 mmol of phosphine per gram of the nanoparticles. Magnetization-field curves recorded at room temperature reveal superparamagnetic behavior. The materials MNP@bpd have proven to be an excellent catalyst after in-situ addition of rhodium (Rh) metal precursor for the hydroformylation reaction of styrene and its derivatives. The extent of reusability of the catalyst has been tested and was found to be active even after seven consecutive cycles.

Base-assisted diazonium activation has been employed to promote gold(i)/(iii) redox catalysis toward allylic oxime cyclization/aryl coupling.

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New Schiff base-coated gold nanoparticles (AuNPs) of type AuNP@L (where L: thiolated Schiff base ligand) have been synthesized and characterized using various spectroscopic techniques. The AuNPs and AuNP@L were imaged by transmission electron microscopy (TEM) and were confirmed to be well-dispersed, uniformly distributed, spherical nanoparticles with an average diameter of 8–10 nm. Their potential applications for chemosensing were investigated in UV-Vis and fluorescence spectroscopic studies. The AuNP@L exhibited selectivity for Fe3+in an ethanol/water mixture (ratio 9 : 1 v/v). The absorption and emission spectral studies revealed a 1 : 1 binding mode for Fe3+, with binding constants of8.5×105and2.9×105 M−1, respectively.

The Rhodium Complex of Bis(diphenylphosphinomethyl)dopamine-coated Magnetic Nanoparticles as an Efficient and Reusable Catalyst for Hydroformylation of Olefins. -A new bis(diphenylphosphinomethyl)dopamine (bpd) ligand is prepared and anchored on the surface of magnetic nanoparticles (MNP). The ligand and the surface functionalized nanoparticles of type MNP@bpd are fully characterized and are proved to be excellent catalysts after in situ addition of the rhodium metal precursor for the hydroformylation reaction of styrene and its derivatives. The extent of reusability of the catalyst is also tested and found to be active even after seven consecutive cycles. -(SHAIKH*, M. N.; BOUOUDINA, M.; JIMOH, A. A.; AZIZ, M. A.; HELAL, A.; HAKEEM, A. S.; YAMANI, Z. H.; KIM, T.-J.; New J. Chem. 39 (2015) 9, 7293-7299, http://dx.