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5-Hydroxymethyl-2-furaldehyde (HMF) was hydrogenated to 2,5-bis(hydroxymethyl)furan (BHMF) in various n-alcohol solvents with more than 99% yield using Ru(OH) x /ZrO2 catalyst. The BHMF in the same solvents was subsequently etherified to give 2,5-bis(alkoxymethyl)furans (BAMFs, four examples) as potential biodiesels with moderate to good yields using Amberlyst-15.

We demonstrate the use of porous phenolsulfonic acid–formaldehyde (PSF) resins as solid-acid catalysts, which showed excellent performance in the esterification of fatty acids without using any solvent or introducing a water-removal process. The catalyst was reused up to 30 times without significant loss of activity.

The metal-free oxidation of organic compounds is one of the most demanding reactions in chemical industries. As such, iodoxybenzoic acid (IBX) is an attractive reagent due to its metal-free oxidative activity. To apply IBX for the alcohol oxidation in water, IBX was immobilized on graphene oxide (GO). GO-supported IBX reagent exhibited excellent performance for alcohol oxidation reaction in water with greater than 90% selectivity. It could be reused without significant loss of oxidative activity.

A photocleavable linker, N -(9-fluorenylmethyloxycarbonyl)-3-amino-3-(4,5-dimethoxy-2-nitrophenyl)propionic acid was synthesized from veratraldehyde, with simple reaction and separation steps. This linker was stable under the normal solid-phase peptide synthesis conditions and rearranged to a labile form when irradiated with UV light (λ = 365 nm). A model peptide sequence (YGGFL) was synthesized and released from solid supports with high efficiency by UV irradiation.

An alkanethiol spacer which is suitable for biointerface was synthesized on 2-chlorotritylchloride (CTC) resin using solid-phase synthesis method. The triethylene glycol (TEG) unit containing building block was immobilized on CTC resin followed by a coupling alkanethiol building block. After dithiothreitol (DTT) treatment and cleavage of the resulting alkanethiol spacer from the resin, the spacer was obtained in a pure form without any purification steps. The TEG-alkanethiol spacer was applied for the DNA hybridization assay on a gold surface, and proved to work well when compared to the commercial spacer.

5-Hydroxymethyl-2-furfural (HMF) was selectively converted to 2,5-diformylfuran (DFF) under mild conditions by polymer-supported IBX amide reagent, thus providing a new platform for the production of highly valuable chemicals from biomass.

A new type of magnetite/silica nanoparticle-supported N-heterocyclic carbene nickel catalyst (Mag-NHC-Ni) was developed from imidazolium with N-picolyl moieties and used as an efficient catalyst in the C―S coupling of various aryl halides with thiols. Moreover, the catalyst was easily recovered from the reaction mixture by simple filtration and recycled with almost consistent activity.

An alkyne-terminated PCDA (10,12-pentacosadiynoic acid) linker, which can undergo a simple click reaction with azide compounds, was synthesized for the purpose of immobilizing various kinds of biomolecular surface ligands on PDA (polydiacetylene) layers. In order to confirm the ability of the linker compound to anchor azide-modified surface ligands, we carried out a model reaction with benzyl azide under typical click-reaction conditions. We were able to confirm that the model reaction proceeded smoothly by observing the color change of PDA, including its thermochromic reversibility.

For efficient peptide synthesis on a glass chip, 20 kinds of pentafluorophenyl (Pfp) esters of nitroveratryloxycarbonyl (NVOC)-protected amino acids were synthesized by using Pfp trifluoroacetate. Simple purification step gave moderate to high yield. The first loading time of each amino acid on glass surface was 30― 60 min. The UV cleavage of the NVOC group was completed within 10 minutes.

Osmium tetroxide was immobilized onto an imidazoli-um-based polymer, poly(1-methylimidazoliummethyl styrene)-sur-face grafted-PS (PS- sg -IM) resin. In order to characterize thepolymer–imidazolium-supported osmium-complex catalysts, Fou-rier transform infrared (FT-IR) spectroscopy, field emission scan-ning electron microscopy (FE-SEM), energy dispersive X-raymicroanalysis (EDX), and inductively coupled plasma-atomicemission spectroscopy (ICP-AES) experiments were carried out,and we verified that the formation of the osmium complex occurredonly on the surface of the polymer support. This polymer catalystswas used in the dihydroxylation of various olefins, revealed excel-lent catalytic activity, and could be reused up to three times Key words: osmium, imidazolium, heterogeneous catalysis Osmium-catalyzed dihydroxylation (DH) and asymmetricdihydroxylation (AD) with chiral ligands are some of themost useful methods used to construct vicinal diols fromolefins. 2 Although the osmium-catalyzed DH and AD re-actions could be applied in the synthesis of drugs, naturalproducts, fine chemicals, etc., the high cost and possiblecontamination of toxic osmium in the final product restrictits use in industry applications.

We found that the spacer and additive play a significant role in the oxidation of alkyl alcohols using polymer-supported IBX-amide reagents. The introduction of the spacer between the polymer support and IBX-amide group improved the initial conversion rate (up to 60% conversion). Furthermore, various alcohol compounds, when reacted with IBX-amide resin in the presence of BF 3 .OEt 2 , were effectively converted into the corresponding aldehydes or ketones within 5-30 minutes in high purities (>94%) at room temperature.

The Heck reaction of aryliodides with n-butylacrylate proceeded in moderate to satisfactory yields when it was catalyzed by polymer-supported N-heterocyclic carbene-palladium complex. This catalyst was able to decrease the reaction time with high efficiency, because the catalytic sites were located only on the surface of the resin. It was also easily recovered quantitatively and reused many times with constant activity.