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The Sm/HgCl2 system reduces β-ketosulfones to the corresponding ketones in moderate to good yield under mild conditions.

The purpose of this study is to solve the problem of low achievement in fabricating sandwich surface-enhanced Raman scattering (SERS) substrates. We demonstrated a highly efficient sandwich structure by the oriented assembly of metal nanoparticles (NPs) on a periodic hexagonal array of metal nanoprisms with 1,4-benzenedithiol (1,4-BDT) as linkers. The metal nanoprism array was prepared by vacuum deposition of metal on a close-packed polystyrene nanosphere pre-patterned substrate. The metal nanoprism array presents different surface properties from the pits left from the removal of polystyrene nanospheres, which causes linkers to selectively adsorb on the metal nanoprism array and sequentially leads to the oriented immobilization of the second-layer metal NPs, avoiding mismatched orientation. These sandwich SERS substrates were characterized by extinction spectroscopy and atomic force microscopy and their enhancement activity was evaluated under different excitation wavelengths. The sandwich structure greatly increases the achievement of 'hot spots' to almost 100% of all the metal nanoprisms and enables a large amplification of SERS signals by a factor of ten. This method has the advantages of simplicity, high efficiency, high throughput, controllability and high reproducibility. It has significance in both the study of SERS substrates and the development of plasmonic devices.

α-Selenonitriles, α-selenoesters, and asymmetrical selenides can be readily obtained from the one-pot reaction of diselenides and active organic halides by a Sm/ZnCl2 system in DMF-H2O.

Metallic samarium can be used in desulfonylation in the presence of glacial acetic acid. The reaction is illustrated here for nine substrates, which include α-phenylsulfonyl cinnamonitriles, β-ketosulfones and phenylsulfonyl cycloheptane.

Diselenides were reduced by samarium diiodide in tetrahydrofuran (THF) to produce samarium selenolate. This selenolate anion reacted smoothly with sodium alkyl thiosulfates and phenylsulfenyl chloride to give selenosulfides in moderate to good yields.

α-Phenylsulfonylcinnamonitriles are readily reduced by Sml2/THF/MeOH to give the corresponding ( E)-cinnamonitriles in good yields under mild conditions.

The Sm/Cp2TiCI2 system reduces arylsulfonyl derivatives to the corresponding disulfides in good yield in refluxing THF.

α-Phenylsulfonylcinnamonitriles are readily reduced by SmI2/THF/MeOH to give the corresponding (E)-cinnamonitriles in good yields under mild conditions.

The Sm/Cp2TiCl2 system reduces arylsulfonyl derivatives to the corresponding disulfides in good yield in refluxing THF.