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The conversion of α-benzocycloalkenones to homologous β-benzocyclo-alkenones containing six, seven and eight-membered rings is reported. This was accomplished via a Wittig olefination-oxidative rearrangement sequence using [hydroxy(tosyloxy)iodo]-benzene (HTIB) is the oxidant, that enables the synthesis of regioisomeric pairs of methyl-substituted β-benzocycloalkenones. The incorporation of carbon-13 at C-1 of the β-tetralone nucleus was also demonstrated. The Wittig-HTIB approach is a useful alternative to analogous sequences in which Tl(NO3)3·3H2O or the Prevost combination (AgNO3/I2) are employed in the oxidation step.

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A concise preparation and characterization of substituted 1-{[(Z)-1-phenyl-2-phenyliodonio)vinyl]oxy}pyridinium ditosylates is presented. Determination of the X-ray crystal structure reveals a pseudo-square planar molecular geometry about iodine.

This chapter provides a digest of the literature reported during 2008 concerning the elemental halogens and noble gases as well as compounds containing these elements in their positive oxidation states. The intent is to highlight discovery and provide insight into current research trends. HighlightsThe 2008 literature for halogen chemistry is highlighted by the first iodonium(V) salt with an electrophilic cation and the first crystallographic evidence for the BrO 2 + cation. Noble gas chemistry advances include the first preparation of HXeOXeH, the smallest known neutral molecule containing two noble gas atoms and the synthesis of [F 5 SN(H)Xe][AsF 6 ] which exhibits one of the shortest Xe-N bonds yet observed. HalogensRecent reviews reflect the importance of organo-fluorine compounds in modern medicinal chemistry. The first offers perspective into the effect of fluorine incorporation into potential drug candidates. 1 The second provides a more directed review of the application of 19 F NMR techniques to elucidate the mechanistic fate of fluoropharmaceuticals in biological systems. 2 Lastly, the recent applications of fluorinated organophosphate chemistry including synthetic methods have been systematically reviewed. 3 With these applications in mind, the fluorination of organic molecules continues to engage researchers. Elemental fluorine was found to react selectively with the tertiary sites of 3b-acetoxy-5a-androstan-17-one to afford three mono-fluorinated products while Selectofluor s exhibited preference for the fluoridation of secondary sites. 4 The reaction of Selectofluor s with acetonide-protected bis-allylsilane results in the diastereoselective preparation of a 3,6-difluorinated-1,7-dienes, key intermediates in the synthesis of novel deoxyfluoro-myo-inositols. 5 Treatment with Selectofluor s of 1,5-anhydro-2-deoxy-hex-1-enitol derivatives has found application in the preparation of chiral 1-fluoro-1-halo-1-iodo-alditols. 6 With the increasing use of fluorous solid phase extraction (FSPE) techniques for the purification of 18 F-labelled radiotracers, significant attention has been focused on tagging and detagging strategies. In the first known detagging process relying on C-H bond formation, fluorous allylsilanes were prepared by cross-metathesis and subsequently subjected to electrophilic fluorodesilylation with Selectfluor s and the resulting allylic fluorides were successfully purified by FSPE. 7 For the first time gold catalysis