Structures of two phenyliodonium ylides

Chemistry of Polyvalent Iodine

“…Several structural types of ylides, however, are sufficiently stable for X-ray structural analysis. Single crystal X-ray structural parameters have been reported for 3-phenyliodonio-1,2,4-trioxo-1,2,3,4-tetrahydronaphthalenide 459 ,851 3-phenyliodonio-2,4-dioxo-1,2,3,4-tetrahydro-1-oxanaphthalenide 460 ,851 mixed phosphonium iodonium ylides 461 852 and 462 ,853 mixed arsonium iodonium ylides 463 ,854 cyclic iodonium ylide 464 ,855 and phenyliodonium bis(trifluoromethanesulfonyl)methide 465 856. In particular, the X-ray structural analysis for phenyliodonium bis(trifluoromethanesulfonyl)methide 465 shows a geometry typical for an iodonium ylide with the I–C ylide bond length of about 1.9 Å and an C-I-C bond angle of 98° 856…”

1,3-Carboboration of iodonium ylides

“…This effect is imparted by secondary C-IÁ Á ÁO bonding. 22 However, this is a weak interaction that should be readily disrupted at elevated temperatures. It is likely these two factors work in a synergistic fashion preventing the aryl transfer.…”

“…Adduct 4 shows short intermolecular OÁ Á ÁI contacts in the solid-state at 2.916 Å and 3.105 Å, slightly longer than those reported for similar compounds in the absence of the B(C 6 F 5 ) 3 adduct (Scheme 4). 22 In order to probe the reactivity of the Lewis acidic borane with the iodonium ylide, a series of computational studies on the formation of 3c were undertaken with the M06-2X functional and LACVP+ basis set (see ESI ‡ for details). Initial calculations probed adduct formation between the borane and the iodonium ylide using the carbonyl O atom as a hard donor.…”

Geminal Dichlorination of Phenyliodonium Ylides of β-Dicarbonyl Compounds through Double Ligand Transfer from (Dichloroiodo)benzene

“…In contrast to the high reactivity of the solution-unstable ylides 4e, 4i and 4j, the iodonium ylide of 4-hydroxycoumarin (7) has exceptional thermal and solution stability, 20 and, as a result, also has decreased relative reactivity. These properties were observed during its dichlorination, as the reaction at 0 °C was poor, and its room temperature reaction required three hours for consumption of the ylide, after which dichloride product 8′ was recovered in 57% yield, presumably via intermediate 8 (Scheme 2, a).…”