Selective and effective oxone-catalysed α-iodination of ketones and 1,3-dicarbonyl compounds in the solid state

Abstract

Selective α-iodination of ketones and 1,3-dicarbonyl compounds was accomplished in the solid state within a very short reaction time with excellent yields using elemental iodine and Oxone as the catalyst, by grinding in a mortar.

Direct Trifluoromethoxylation without OCF3‐Carrier through In Situ Generation of Fluorophosgene

“…13 C NMR (400 MHz, CDCl 3 ): δ=2.0, 128.9, 129.1, 133.2, 133.9, 193.0. In accordance with previous reports [32] …”

Molecular Iodine-Mediated α-Iodination of Carbonyl Compounds

“…Goswami and co-workers employed molecular iodine and oxone ® (a stable ternary mixture of KHSO 5 /KHSO 4 and K 2 SO 4 in a 2:1:1 molar ratio) as catalyst to effect selective αiodination of cyclic ketones such as tetralone, cyclopentanone, cyclohexanone and cyclodecanone to afford within 3 minutes the corresponding monoiodo derivative in 91%, 96%, 96% and 93% yield, respectively. 28 Since iodine is completely consumed into the organic molecules in the absence of solvent with no need for tedious work-up and purification requirements, this methodology represents a suitable alternative to the use of I 2 -DME, I 2 -SeO 2 or I 2 -CAN mixture. Iodine-oxone ® mixture at room temperature was also found to effect selective αiodination of a series of 1,3-dicarbonyl compounds 20 (1,3diketones, β-ketoesters and diethyl malonate) within 2-3 minutes to afford mono-iodo derivatives 21 in excellent yields (Scheme 9).…”

“…Iodine-oxone ® mixture at room temperature was also found to effect selective αiodination of a series of 1,3-dicarbonyl compounds 20 (1,3diketones, β-ketoesters and diethyl malonate) within 2-3 minutes to afford mono-iodo derivatives 21 in excellent yields (Scheme 9). 28 Iodinated 1,3-dicarbonyl derivatives would probably decompose during aqueous work or purification by column chromatography and have yet to be synthesised using the other reagents described above.…”

“…α-Iodination of 5,6-disubstituted cyclohexenone derivatives with iodine was successfully promoted by 4-(dimethylamino)pyridine (DMAP) in dichloromethane instead of pyridine which resulted in half conversion. 41 Perhaps, iodine-oxone ® mixture previously employed for selective α-iodination of 1,3-dicarbonyl compounds 28 could be employed in this case to avoid the use of basic conditions involving pyridine or DMAP.…”

Solid-Phase Organic Synthesis of α-Iodo Ketones using Recyclable Resin-Bound Selenium Bromide

“…5 Alternatively, the iodoniumdonating systems such as KI/KIO 3 /H 2 SO 4 6 and NaI/H 2 O 2 / H 2 SO 4 7 were used for α-iodination of ketones. Additionally, molecular iodide 8 or with oxidising agents such as I 2 /HgCl 2 , 9 I 2 /SeO 2 /AcOH, 10 I 2 /N-F reagent, 11 I 2 /oxone, 12 15 and I 2 /m-iodobenzoic acid 16 were used to access these compounds. Ionic liquids, 17 microwave irradiation 18 and hypervalent iodine reagents 19 have also been utilised for similar transformations.…”