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• 14633-55-7 cyclopropyl 4-methylphenyl sulfide 

Relevant academic research and scientific papers

Modular Polyoxometalate–Layered Double Hydroxides as Efficient Heterogeneous Sulfoxidation and Epoxidation Catalysts

The selective sulfoxidation of sulfides and the epoxidation of olefins are two types of important organic reactions, and the corresponding products of sulfoxides, sulfones and epoxides are used widely as raw materials in industrial processes. The fabrication of one efficient catalyst for both reactions remains a challenging task. We report the preparation of a highly efficient heterogeneous catalyst Mg3Al-ILs-La(PW11)2 using an exfoliation/assembly approach. The catalyst was characterised by FT-IR spectroscopy, XRD, thermogravimetric and differential thermal analysis, BET measurements, X-ray photoelectron spectroscopy, 29Si cross-polarisation magic-angle spinning NMR spectroscopy, 27Al magic-angle spinning NMR spectroscopy, SEM, high-resolution TEM, and energy-dispersive X-ray spectroscopy. The designed catalyst showed a high efficiency and selectivity for the sulfoxidation of sulfides and the epoxidation of olefins under mild conditions at a production rate of 208 and 31 mmol g?1 h?1, respectively. Moreover, Mg3Al-ILs-La(PW11)2 can be recycled and re-used at least five times without a clear decrease of its catalytic activity. The scaled-up experiments revealed that the catalyst retained its efficiency and robustness, which demonstrates the great potential of the catalyst for industrial applications.

Chemistry of oxaziridines. 17. N-(phenylsulfonyl)(3,3-dichlorocamphoryl)oxaziridine: A highly efficient reagent for the asymmetric oxidation of sulfides to sulfoxides

The synthesis, structure, and enantioselective oxidations of a new chiral N-sulfonyloxaziridine 12c [3,3-dichloro-1,7,7-trimethyl-2'-(phenylsulfonyl)spiro[bicyclo[2.2.1]heptane-2, 3'-oxaziridine]] are reported. This oxidant, which exhibits remarkably high and predictable ee's for the enantioselective oxidation of prochiral sulfides to sulfoxides, is prepared in three steps from (+)- or (-)-camphor in 50% overall yield. Steric effects are primarily responsible for the molecular recognition and are predictable using a simple active-site model where the nonbonded interactions between the RL and RS groups of the sulfide (RL-S-RS) and the active-site surface are minimized in a planar transition-state structure. The fact that alkyl aryl sulfides give high ee's in nonpolar solvents suggests that there is also a stereoelectronic component to the molecular recognition. High ee's (>90%) are anticipated for those sulfides where the difference in size of the groups directly bonded to the sulfur atom is large, i.e., aryl, tert-butyl vs CH2R (R = H, alkyl, benzyl, etc). The X-ray structure and studies with the dihydro, difluoro, and dibromo oxaziridines 12a, 12b, and 12d reveal that the exceptional enantioselectivities displayed by 12c are a consequence of a molecular cleft or groove, defined by the oxaziridine chlorine atoms and phenylsulfonyl group, on the active-site surface.