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AbslmcL Diffusion of lit-based and PFZ-based species in an amorphous p o w e x eleclmlyle has teen explored by pulsed-Beld-gradient (PFG) nuclear magnetic m n a n c e . n e erperiments were undertakn over a range of salt mncentrations and temperature enending 10 lower values of both wriables than in prwious studies Features of the lesults include a demonstration of different mechanisms lor anion and cation lranspon at high concentration, as shown bj their different temperature dependences, a reduced sensitivity of cation diffusion to salt concentration and a failure of the Nemst-Einstein relationship Cation hopping terween ionic dusters and the diffusion of neutral ion pairs are advanced as micmsmpic mechanisms lo aplain the data.

[reaction: see text] A new synthetic procedure for aminohalogenation of olefins has been developed for the preparation of vicinal haloamine derivatives in high yields by using Cu, Mn, or V catalysts with p-toluenesulfonamide (TsNH(2)) and N-bromosuccinimide (NBS) as nitrogen and bromine sources, respectively. Unprecedented regio- and stereoselectivity (anti:syn > 99:1) toward the aminohalogenation process is shown for olefinic substrates as well as transition metal catalysts.

[reaction: see text] LiBr catalyzes efficiently the dihydroxylation of alkenes to afford syn and anti diols with excellent diastereoselectivity depending upon the use of NaIO(4) (30 mol %) or PhI(OAc)(2) (1 equiv), respectively, as the oxidants. The oxidation of non-benzylic halides has been achieved for the first time to afford the corresponding diols in excellent yields.

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The investigation of new oxidative transformations for the synthesis of carbon-heteroatom and heteroatom-heteroatom bonds is of fundamental importance in the synthesis of numerous bioactive molecules and fine chemicals. In this context, NaIO4, an exciting reagent, has attracted increasing attention enabling the development of these unprecedented oxidative transformations that are difficult to achieve otherwise. Thus, NaIO4 has been successfully explored as a versatile oxidant for a variety of fundamental organic transformations such as C-H activation, oxidative functionalization of alkenes and other interesting oxidative transformations and its application in the synthesis of bioactive natural products. This review summarizes recent developments in this area with NaIO4 as a versatile oxidant and brings out many challenges that still remain elusive for the future.

[reaction: see text] NaIO(4) oxidizes alkali metal halides efficiently in aqueous medium to halogenate alkenes and aromatics and produce the corresponding halo derivatives in excellent regio and stereoselectivity. The system also demonstrates the asymmetric version of bromo hydroxylation using beta-cyclodextrin complexes, resulting in moderate ee.

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