Suarez reagent

De Armas, P., Carrau, R., Concepcion, J. I., Francisco, C. G., Hernandez, R., Suarez, E. Synthesis of 1,4-epimine compounds, lodosobenzene diacetate, an efficient reagent for neutral nitrogen radical generation. Tetrahedron Lett. 1985, 26, 2493-2496. 

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. 

W.T. Suarez, H.J. Vieira, O. Fatibello-Filho, Generation and destruction of unstable reagent in flow injection system determination of acetylcysteine in pharmaceutical formulations using bromine as reagent, J. Pharm. Biomed. Anal 37 (2005) 771. 

The third modification of the Hunsdiecker reaction is the so-called Sudrez modification,21 where the steroidal acids were treated with hypervalent iodine reagent in CCI4 to prepare steroidal chloride. The Sudrez modification also works for bromination using iodobenzene diacetate, bromine, and CH2Br2 as the solvent under irradiation as exemplified by transformations 14—>15.22 Unlike many variations described before, the Suarez modification tolerates a variety of functional groups. 

In addition, the reaction between hypervalent iodine reagents such as iodosyl-benzene or its diacetate derivative with molecular iodine has been employed frequently in aliphatic amination reactions. These processes start from an initial formation of an alkyl hypoiodite derivative, which can promote subsequent radical amination pathways. An excellent use of this concept is the Suarez methodology for the generation of diversified aminated carbohydrate structures [80-86]. Although the hypervalent iodine reagent is not directly involved in the amination reaction, the efficiency of the method deserves mentioning within the present chapter. It was recently extended to catalytic transformations [87],... 

Althaus, M. Mahmood, A. Suarez, J. R. Thomas, S. R Aggarwal, V. K. Application of the Lithiation-Borylation Reaction to the Preparation of Enantioenriched Allylic Boron Reagents and Subsequent In Situ Conversion into 1,2,4-Trisubstituted Homoallylic Alcohols with Complete Control over All Elements of Stereochemistry. /. Am. Chem. Soc. 2010,132,4025-4028. 

This selenium reagent, Ph2Se(OH)OAc, was also proposed by Suarez in 1988. The reaction is carried out in cyclohexane at the reflux temperature (80°C). The active species in the formation of alkyl hypoiodites could again be acetyl hypoiodite. 

More recendy, spiroacetal formation has been successfully exploited by Suarez and collaborators in the synthesis of a number of chiral spiroacetals and dispiroacetals from carbohydrates (Schemes 33,34, and 35). The approach was also used to synthesize anomeric spironucleosides (Scheme 36). The best yields were achieved with the DIB-iodine reagent. Some typical examples are shown in Schemes 30 through 36. 

Armas, d.R, Francisco, C.G., and Suarez, E, Reagents with hypervalent iodine formation of convenient chiral synthetic intermediates by fragmentation of carbohydrate anomeric alkoxy radicals, Angew. Chem. Int. Ed. Engf., 31, 111, 1992. 

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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