Hypervalency organoiodine

In recent years, a variety of hypervalent iodine reagents have been available. The versatility of these hypervalent organoiodine reagents in organic synthesis has been well recognized. Diaryliodonium salts constitute an important reagent class for the transfer of aryl groups. These iodonium ion salts have been used effectively in C-arylation of a variety of nucleopohiles.112 The arylation of the anion of nitroalkanes with diaryliodonium salts was already reported in 1963.113... 

M. Ochiai, Y. Nagao Hypervalent organoiodine compounds in organic synthesis reaction with organosilicon and tin [12]... 

D. Wang Application of hypervalent organoiodine compounds in synthesis [17]... 

The Synthesis of Heterocyclic Compounds with Hypervalent Organoiodine Reagents... 

Applications to the synthesis of heterocyclic compounds of hypervalent organoiodine reagents are covered by Gerald Koser (University of Akron, Ohio) who is well known for his own book in the field. The present review provides continuity with the earlier comprehensive treatment of the subject by Moriarty and Prakmash in Volume 69 of Advances in Heterocyclic Chemistry, which covered the field up through 1996. 

Hypervalent organoiodine compounds have found wide utility in organic synthesis. Primary and secondary alcohols can be oxidized to aldehydes and ketones with the 12-1-5 compound (28), according to equation (29). a-Hydroxy dimethyl acetals can be synthesized under basic conditions with the 10-1-3 reagent PhI(OAc)2 (equation 30). The topic... 

Ynol tosylates are synthesized from terminal alkynes via a unique sequence (equation 10). The hypervalent organoiodine compound 32, prepared by treatment of iodosoben-zene diacetate with /i-toluenesulfonic acid, reacts with the terminal alkynes 31 to give the iodonium tosylates 33, which are then treated with 10 mol% of CuOTf or AgOTf to afford the ynol tosylates 34. Finally, the ynol tosylates 34 are converted into lithium ynolates 35 by treatment with MeLi. The ynolates are trapped with r-butyldimethylsilyl chloride, triethylgermyl chloride and tributylstannyl chloride to give the silyl ynol ethers 36, the germyl ketenes 37 and the stannyl ketene 38. ... 

The generation of alkoxyl radicals from alcohols is an important process which has been used for remote functionalization via hydrogen atom abstraction and for rearrangement via -fragmentation. Hypervalent organoiodine compounds have been applied with success in this type of chemistry. More recently, tetravalent selenium compounds have been used for the same purpose [120]. An efficient way of making ether linkage from non-functionalized alcohols has been developed. The conversion of the alcohol 158 to the ether 159 is a key step in the synthesis of (-l-)-8-deoxyvernolepin [Eq. (51)] [121]. This transformation is best... 

The oxidative Hofmann rearrangement of primary carboxamides occurs by use of lead tetraacetate (LTA) and several hypervalent organoiodine compounds IF5 (28), PhI(OCOCP3)2 (29), PhI(OH)OTs (30) and PhIO (31) under mildly acidic conditions. 

Hydroxy(tosyloxy)iodobenzene (HTIB 30) is another hypervalent organoiodine compound which acts as a Hofmann reagent, converting aliphatic carboxamides to alkylammonium tosylates in refluxing acetonitrile (equation 23). 

Dorta, R. L., Francisco, C. G., Suarez, E. Hypervalent organoiodine reagents in the transannular functionalization of medium-sized lactams synthesis of 1-azabicyclo compounds. J. Chem. Soc., Chem. Common. 1989,1168-1169. 

Syntheses of heterocyclic compounds with hypervalent organoiodine reagents 04AHC(86)225. 

Barton, D.H.R., Jaszbetenyi, J.C., Lin, W. and Shinada, T. (1996) Oxidation of hydrazones hy hypervalent organoiodine reagents regeneration of the carbonyl group and facile syntheses of a-acetoxy and a-alkoxy azo compounds. Tetrahedron, 52, 14673-14688 (1997) Tetrahedron, 53, 14821, (erratum) Barton, D.H.R., Jaszbetenyi, J.C., Lin, W. and Shinada, T. (1996) The invention of radical reactions. Part XXXVI. Synthetic studies related to 3-deoxy-D-manno-2-octulosonic acid (KDO) Tetrahedron, 52, 2717-2726. 

Koser, G. F., The Synthesis of Heterocyclic Compounds with Hypervalent Organoiodine Reagents, 86, 225. 

The structural aspects of polyvalent iodine compounds were previously summarized in several books and reviews [20, 30, 32, 127]. In general, the molecular structure of and -iodanes is predetermined by the nature of hypervalent bonding discussed in Section 1.3. The key stmctural features of the hypervalent organoiodine compounds available from numerous X-ray data may be summarized as follows ... 

Acetylenic tosylates have now been prepared for the first time, and again hypervalent organoiodine compounds are important inter-... 

Hypervalent organoiodine reagents are diverse and have a rich history [1-7]. As many of these reagents are easily prepared, they are heavily utilized for a variety... 

Hernandez, R., Marrero, J.J., Melian, D., and Suarez, E., Hypervalent organoiodine reagents in the P-fragmentation of bicycHc carbinolamides leading to imides. Tetrahedron Lett., 29, 6661,1988. 

De Armas, R, Concepcion, J.I., Francisco, C.G., Hernadez, R., Salazar, J.A., and Suarez, E., Intramolecular hydrogen abstraction. Hypervalent organoiodine compounds, convenient reagents for alkoxy radical generation, J. Chem. Soc., Perkin Trans. 1,405, 1989. 

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