The air and moisture stable fluoroiodane 8, readily prepared on a 6 g scale by nucleophilic fluorination of the hydroxyiodane 7 with TREAT-HF, has been used as an electrophilic fluorinating reagent for the first time to monofluorinate 1,3-ketoesters and difluorinate 1,3-diketones 10 in good isolated yields.In late 2011, Ritter reported the first electrophilic fluorination using the fluoride anion in a transfer fluorination between two palladium species. 1 An alternative, non-metal based strategy could be envisaged using cyclic hypervalent iodine(III) 15 compounds which have been shown to be mild, non-toxic and selective reagents for halogenation. Our research group is interested in designing new methods for introducing fluorine into organic molecules 5 because of the importance of incorporating fluorine into drug candidate 35 molecules. 6 Since Banks first reported SelectFluor in 1992, 7 the fluoraza reagents have become increasingly popular electrophilic fluorinating reagents because they are commercially-available, shelf-stable powders that can be used to fluorinate a wide variety of substrates. 8 The main disadvantage of these electrophilic 40 fluorinating reagents, however, is that they are very expensive because they are normally made from elemental fluorine. ____________________________________________________ Alternative reagents such as (difluoroiodo)arenes have been prepared from aqueous HF, but they are extremely moisture sensitive and are commonly used as a freshly prepared solution, without isolation, or they can be generated in situ. 9 Inspired by Togni's seminal work on electrophilic trifluoromethylation, 3 we 55 were interested in developing a new class of stable fluorinating reagents based on the cyclic hypervalent iodine(III) skeleton, but generated from cheap sources of fluoride. Here, we will report three different methods for the preparation of an air and moisture stable fluorinated hypervalent iodine reagent 8 and preliminary 60 results on its' fluorination of a series of 1,3-dicarbonyl substrates.Scheme 2 Synthesis of the fluoroiodane 8 using TREAT-HF

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A series of N,N'-dialkyl-4,13-diaza-18-crown-6 lariat ethers possessing two C8H17 (2), (CH2)3C8F17 (3), (CH2)3C10F21 (4), and (CH2)2C8F17 (5) side arms were synthesized in good yields by N-alkylation of 4,13-diaza-18-crown-6. Potassium picrate could be extracted from an aqueous solution into an organic phase by all of the perfluoroalkylated macrocycles demonstrating their potential to be used as phase-transfer catalysts, and preliminary studies on a classical nucleophilic substitution established that they each gave higher catalytic activities under solid-liquid than under liquid-liquid phase-transfer conditions. The light fluorous macrocycles gave similar, if not better, catalytic activity compared to the parent, non-fluorinated phase-transfer catalyst 2 under solid-liquid conditions in conventional organic solvents in both an aliphatic and an aromatic nucleophilic substitution. N,N'-Bis(1H,1H,2H,2H,3H,3H-perfluoroundecyl)-4,13-diaza-18-crown-6 (3) was recycled six times in the iodide displacement reaction of 1-bromooctane and four times in the fluoride displacement reaction of 2,4-dinitrochlorobenzene using fluorous solid-phase extraction without any loss in activity.

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