Diphenyliodonium

The interaction of iodoaobenzene and iodoxybenzene in the presence of aqueous sodium hydroxide yields the soluble diphenyllodonium iodate (IV) upon adding potassium iodide solution, the sparingly soluble diphenyliodonium iodide (V), analogous to ammonium iodide is precipitated ... 

I) The filtrate contains some diphenyliodonium salts these may be recovered as the sparingly soluble diphenyliodonium iodide (about 8 g.) (Section IV,27) by the addition of potassium iodide. 

Benzyne, generated from diphenyliodonium 2-carboxyIate, reacts with various thiophenes by addition to the sulfur and /3-carbon to give, after loss of an acetylene moiety, benzo[Z)]thiophenes in low (<4%) yield (Scheme 52) (81CC124). 

Phenyl radicals can be generated by the thermal decomposition of lead tctrabcnzoate, phenyl iodosobenzoate, and diphenyliodonium hydroxide,- - and by the electrolysis of benzoic acid.- These methods have been employed in the arylation of aromatic compounds, including heterocycles. A method of promise which has not been applied to the arylation of heterocycles is the formation of aryl radicals by the photolysis of aromatic iodides at 2537... 

Mo(CO)2(i -COCy)l followed [83JCS(CC)55]. Oxidation of [(i -Tp )Mo(CO)3l] with diphenyliodonium in methyl iodide gives [(>j -Tp )Mo(CO)2(i -COMe)], and in THF this reaction becomes possible even in the absence of an oxidant (89JA2550, 89JCCS31). 

Diethylammonium chloride, reaction with chloroform to give 1,1,3-trichloro- -nonane, 45,104 Diethylazelate, 46, 31 Diethylbenzene as solvent for decomposition of diphenyliodonium-2-carboxylate in preparation of... 

Hydroxy(tosyloxy)iodobenzene 2014 reacts with phenyltrimethylsilane 81 in boiling acetonitrile to give diphenyliodonium tosylate 2015 and trimethylsilanol 4 or HMDSO 7 [184, 185]. Likewise, treatment of 2,5-bis(trimethylsilyl)furan 2016 with 2014 in boiling acetonitrile/methanol affords 78% iodonium tosylate 2017 and trimethylsilanol 4 [185]. In the presence of Bp3-OEt2 iodosobenzene oxidizes allyl-trimethylsilanes such as 2018 to unsaturated aldehydes such as 2019 in 63% yield, with formation of iodobenzene and trimethylsilanol 4 [186]. Analogously, vinyltrimethylsilanes such as (Z)-l-trimethylsilyl-2-phenylethylene 2020 afford, via 2021, acetylenes such as phenylacetylene in 61% yield and iodobenzene and trimethylsilanol 4 [187] (Scheme 12.54). 

With benzenediazonium-2-carboxylate or diphenyliodonium-2-carboxylate monohydrate, benzyne precursors, 11 yield 1818 (Scheme 34). 

Materials. The 1-propanol, glycerol and anthracene were obtained from Aldrich Chemical Company and were used as received. As in a previous study,17 a commercially available bis-(4-dodecylphenyl) iodonium hexafluoroantimonate salt (UV9310C GE Silicones) was used as the initiator. In this initiator, various dodecyl isomers have been attached to the phenyl rings of the diphenyliodonium salt to impart solubility in the monomer and do not effect the reactivity of the initiator.1 All studies were performed with an order of magnitude excess of initiator relative to anthracene. 

DiphenyI-3-ethylpentane, 48, 82 Diphenyliodonium-2-carboxylate, as reagent for generation of benzyne,... 

Pentanedione, with sodium amide and diphenyliodonium chloride to give 1-phenyl-... 

Phenylation, of 3-diketones with diphenyliodonium chloride, 51, 131 of ketoesters with diphenyliodonium chloride, 51, 131 of nitroalkanes with diphenyliodonium chloride, 51, 132 PHENYLATION WITH DIPHENYL-... 

Sodium, with l-bromo-3-chloro-cyclobutane to give bicyclo [l.l.O]butane, 51, 55 Sodium amalgam, 50, 50, 51 Sodium amide, with 2,4-pentane-dione and diphenyliodonium chloride to give l-phenyl-2, 4-pentanedione, 51, 128 Sodium azide, 50, 107 with mixed carboxylic-carbonic anhydrides, 51, 49 Sodium borohydride, reduction of erythro-3-methanesulfony-loxy-2-butyl cyclobutanecar-boxylate, 51, 12 reduction of 2-(1-phenylcyclo-pentyl)-4,4,6-trimethyl-5,6-dihydro-1,3(4H)-oxazine to 2-(1-phenylcyclopentyl)-4,4, 6-trimethyltetrahydro-l,3-oxazine, 51, 25 Sodium cyanoborohydride, used... 

A colourless salt is precipitated from the alkaline filtrate (without the washings) by passing in sulphur dioxide, which serves to reduce the iodic acid produced. After the mixture has stood for some time, the salt, diphenyliodonium iodide, is collected at the pump and recrystallised from hot water. 

The basic function of the iodine in the iodonium bases, which correspond exactly to the ammonium, sulphonium, and oxonium bases, is most interesting. A molecule of diphenyliodonium iodide has the same atoms as two molecules of iodobenzene and decomposes on heating with liberation of heat (contrast other dissociations such as those of N204, NH4C1, PC15) into two moles of C8H8I. Test with a small sample in a tube. 

Elimination, of arenesulfinate ion from 1 -alkyl-2-arylsulfonyl-5-amino-4-pyrazoline salts, 48,12 of carbon dioxide and iodobenzene from diphenyliodonium-2-car-boxylate to generate benzyne, 46,107... 

---