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N-Acylated perfluoroalkylated sulfoximines are synthe-sized easily from the corresponding free NH-sulfoximines on reac-tion with acid chlorides. This mild procedure is extended to diacid chlorides for the preparation of dimeric N-bridged sulfoximines and to reactions with chloroformates, carbamoyl chlorides, chlorothio-noformates and thiocarbamoyl chlorides as electrophiles. [ABSTRACT FROM AUTHOR]

A selective gold(I)-catalyzed synthesis of chiral aza-proline derivatives has been developed by ring closure of enantioenriched α-hydrazino esters bearing an alkyne group. These are easily prepared through a synthetic strategy involving two key steps: organocatalyzed electrophilic amination of pent-4-ynal with dialkyl azodicarboxylate promoted by L-proline and functionalization of the triple bond by Sonogashira cross-coupling. This strategy allowed the preparation of a range of enantioenriched α-hydrazino esters that underwent ring closure by using Ph3PAuCl/AgBF4 as a catalytic system. Under these conditions, 5-exo-dig cyclization was favored over 6-endo-dig and aza-proline derivatives were obtained in good yields without epimerization at the stereogenic center. Influence of the catalytic system, hydrazine protecting group and alkyne substitution on the cyclization step has also been investigated. [ABSTRACT FROM AUTHOR]

The electroreduction of SF 6 is shown at ambient temperature in acetonitrile using an array of platinum microelectrodes to improve the electrical detection. Its half reduction potential occurs at -2.17 V vs Fc + /Fc. The exact number of electrons for the full consumption of sulfur hexafluoride was determined and this gas further quantitatively transformed into environmentally benign fluoride anion and sulfur by electrochemical reduction., (Copyright © 2020, Bouvet et al.; licensee Beilstein-Institut.)

Among halogenated aromatics, iodoarenes are unique in their ability to produce the bench-stable halogen(III) form. Earlier, such iodine(III) centers were shown to enable C-H functionalization ortho to iodine via halogen-centered rearrangement. The broader implications of this phenomenon are explored by testing the extent of an unusual iodane-directed para C-H benzylation, as well as by developing an efficient C-H coupling with sulfonyl-substituted allylic silanes. Through the combination of the one-shot nature of the coupling event and the iodine retention, multisubstituted arenes can be prepared by sequentially engaging up to three aromatic C-H sites. This type of iodine-based iterative synthesis will serve as a tool for the formation of value-added aromatic cores., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

As early as 1991 Ochiai et al. reported that an acid-activated form of phenyliodine diacetate, PhI(OAc) 2 , undergoes a reaction with propargyl-silanes, germanes and stannanes to give the ortho-propargyl iodobenzene. This formal C-H alkylation was proposed to take place through an unusual (even to date) iodonio-based [3,3] rearrangement of an intermediate allenylsilane. Although this mechanistic principle has been invoked in related iodane-directed C-H coupling reaction, some underlying principles have remained unaddressed, and the reaction rarely employed. Herein, DFT evidence for a mechanism best described as iodine-guided electrophilic aromatic substitution is presented. Using a newly optimized reaction protocol that significantly reduces the undesired reduction process, the potency of the method is showcased through the synthesis of >40 structurally diverse ortho-iodo propargyl (or allenyl) arenes., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)