Phenyliodonium diacetate oxidant

Phenyliodonium diacetate,274 275 and phenyliodonium to-trifluoroacetate, 276 are also useful oxidants for converting amides to carbamates. 

Fragmentation of alkoxy radicals finds use in construction of medium-size rings.364 One useful reagent combination is phenyliodonium diacetate and iodine.365 The radical formed by fragmentation is normally oxidized to the corresponding carbo-cation and trapped by iodide or another nucleophile. 

The reactions can also be effected by phenyliodonium diacetate.377 A mechanistic prototype can be found in the conversion of pentanol to 2-methyltetrahydrofuran. The secondary radical is most likely captured by iodine or oxidized to the carbocation prior to cyclization.378... 

In addition to conventional generation of carbenes from nitrodiazo compounds (22) (79), target intermediates C can be prepared by oxidation of functionalized AN CH2XNO2 with phenyliodonium diacetate. The reactions of Rhodium intermediates with certain olefins afford the corresponding cyclopropanes (23). The cycloaddition reaction was performed in the presence of a catalyst. (The successful synthesis of nitrocyclopropanes from trinitromethane derivatives and nitroacetic ester was also documented (81)). 

Phenyliodonium diacetate,182 183 184 phenyliodonium trifluoroacetate,185 and iodosobenzene diacetate186 187 are also useful oxidants for amides. 

The accessibility of position 9 becomes much higher when an activating group, such as an OH, is present in position 10. Although 10-hydroxycamptothecin (8) is available in small amounts from the plant material, two efficient preparations of this compound were developed, via catalytic reduction of CPT in acid medium to a tetrahydroquinoline, followed by selective oxidation with lead tetraacetate [8], or phenyliodonium diacetate [27], or via a photochemical rearrangement of camptothe-... 

The oxidation of a ( )-flavanone with Tl(ni) nitrate, Pb tetracetate, phenyliodonium diacetate (PIDA), or [hydroxyl(tosyloxy)iodo]benzene in trimethyl orthofonnate affords the corresponding ( )-2,3-dihydrobenzo[h]furan derivative as a major product. The structures, including the relative stereochemistry, and a plausible mechanism of formation are reported. The preferred formation of a flavone from the ( )-flavanone by PIDA is explained by quantum-chemical calculations on the intermediate formed by the addition of this reagent to the enol ether derivative of the ( )-flavanone." Formation of mixed anhydrides by rapid oxidation of aldehydes, activated by pivalic acid, Bu OCl in presence of pyridine and MeCN is catalysed by TEMPO (2,2,6,6-tetramethylpiperidin-l-oxyl). The anhydrides can be converted in situ to esters, secondary, tertiary or Weinreb amides in high yield. Oxidation of the aldehyde to 2-propyl esters is also possible using only catalytic amounts of pivalic acid." ... 

Oxidation of carbonyl compounds with organo-hypervalent iodine reagents has been reviewed. The hypervalent iodine oxidation of several a-substituted 2,4-dihydroxyacetophenones (12) (Scheme 6) using phenyliodonium diacetate (PIDA) proceeds via rearrangement of an iodonium ylide (13) to afford novel o-iodophenoxy ethers (14). ... 

Xu J-H, Jiang Q, Guo C-C (2013) Phenyliodonium diacetate mediated direct synthesis of benzonitriles from styrenes through oxidative cleavage of C=C bonds. J Oig Chem 78 (23) 11881-11886... 

Murakata, M., Yamada, K., and Hoshino, O. (1998) Studies on synthesis of araplysillins via oxidative cyclisation of o-phenolic oxime-add derivatives using phenyliodonium diacetate. Heterocycles, 47,921-931. 

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