1-Fluoro-3,3-dimethyl-1,3-dihydro-1λ3-benzo[d][1,2]iodoxole

The asymmetric unit of the title compound, C9H10FIO, contains two independent molecules which are weakly bound by intermolecular O⋯I interactions [3.046 (4) and 2.947 (4) Å]. The two covalent I—F bonds are slightly longer than the two I—O bonds.

Experimental Crystal data

Data collection
Enraf-Nonius CAD-4 diffractometer Absorption correction: scan (NRCVAX;Gabe et al., 1989] T min = 0.337, T max = 0.422 3408 measured reflections 3408 independent reflections 2833 reflections with I > 2(I) 1 standard reflections every 100 reflections intensity decay: none Refinement R[F 2 > 2(F 2 )] = 0.030 wR(F 2 ) = 0.073 S = 1.05 3408 reflections 217 parameters H-atom parameters constrained Á max = 0.64 e Å À3 Á min = À1.22 e Å À3 Table 1 Selected bond lengths (Å ). Hypervalent iodine compounds have received a growing attention in recent years. This is not surprising considering that these reagents are polyvalent electrophiles and mild oxidants (Zhdankin & Stang, 2002;Wirth, 2005). In this family, haloiodanes are interesting yet under exploited electrophilic halogen sources. A research project currently underway in our group aims to exploit haloiodanes as electrophilic halogen sources. We developed a synthesis to obtain the title compound in order to evaluate and compare its reactivity with its chloro and bromo analogs. This is the first reported synthesis of the title compound.
In the crystal structure, two independent molecules, as shown in Fig. 1, are weakly bound by O···I interactions  (Braddock et al., 2006) analogs. This is consistent with the trans effect behavior described in a variety of hypervalent λ 3 -iodane compounds (Ochiai et al., 2006). In contrast to the bromo analog, the title compound was found to be completely unreactive for the fluorination of anisole. While the title compound is a stable solid, caution must be taken when drying the crude solution. The use of anhydrous MgSO 4 to dry the solution results in the displacement of the fluorine by a sulfate dianion. Drying by co-evaporation with benzene prevents this side reaction.
A more in-depth study of the reactivity of this novel fluoroiodane is currently underway.
Experimental 2-(2-Iodophenyl)-propan-2-ol (164 mg, 0.63 mmol) was dissolved in MeCN (3 ml) and SelectFluor (289 mg, 0.81 mmol) was added in one portion. The reaction was then stirred at room temperature for 16 h. The mixture was concentrated under reduced pressure. The crude product was dissolved in CH 2 Cl 2 (10 ml), washed once with water (10 ml), and concentrated under reduced pressure. The crude product was dried by coevaporation with benzene. Crystals were grown by slow diffusion of a pentane solution on a CH 2 Cl 2 solution of the title compound at room temperature.

Refinement
The hydrogen atoms were placed at idealized calculated geometric positions and refined isotropically using a riding model.  The asymmetric unit of the title compound, showing 30% probability displacement ellipsoids. The I···O interactions are shown by dotted lines. H atoms are depicted as circles of arbitrary size.  (Flack, 1992) program was used for centering, indexing, and data collection. One standard reflection was measured every 100 reflections, no decay was observed during data collection. The data were corrected for absorption by empirical methods based on psi scans and reduced with the NRCVAX (Gabe, 1989) programs. They were solved using SHELXS97 (Sheldrick, 2008) and refined by full-matrix least squares on F2 with SHELXL97 (Sheldrick, 2008). The non-hydrogen atoms were refined anisotropically. Refinement of F 2 against ALL reflections. The weighted Rfactor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and Rfactors based on ALL data will be even larger.