Prevost method

Alkenes can be oxidized to diols by the Prevost method, which involves the reaction of an alkene with iodine and silver acetate. The frans-1,2-diacetate formed first on hydrolysis gives frans- 1,2-diols (Scheme 7.26). In the Woodward variation of the Prevost reaction, the monoester is formed under aqueous conditions, which on hydrolysis gives ds-diol. 

Prevost method The overall //7//-hydroxylation of an alkene achieved by treating the alkene with a 1 2 molar ratio of iodine and silver benzoate, followed by hydrolysis. Overall. syw-hy droxy 1 ation may be achieved by the method of Woodward. 

The same result can be achieved in one step with w-chloroperoxybenzoic acid and water. Overall anti addition can also be achieved by the method of Prevost. In... 

The preparation of Pans-1,2-cyclohexanediol by oxidation of cyclohexene with peroxyformic acid and subsequent hydrolysis of the diol monoformate has been described, and other methods for the preparation of both cis- and trans-l,2-cyclohexanediols were cited. Subsequently the trans diol has been prepared by oxidation of cyclohexene with various peroxy acids, with hydrogen peroxide and selenium dioxide, and with iodine and silver acetate by the Prevost reaction. Alternative methods for preparing the trans isomer are hydroboration of various enol derivatives of cyclohexanone and reduction of Pans-2-cyclohexen-l-ol epoxide with lithium aluminum hydride. cis-1,2-Cyclohexanediol has been prepared by cis hydroxylation of cyclohexene with various reagents or catalysts derived from osmium tetroxide, by solvolysis of Pans-2-halocyclohexanol esters in a manner similar to the Woodward-Prevost reaction, by reduction of cis-2-cyclohexen-l-ol epoxide with lithium aluminum hydride, and by oxymercuration of 2-cyclohexen-l-ol with mercury(II) trifluoro-acetate in the presence of ehloral and subsequent reduction. ... 

Synthesis of 31 by Method I (107,108) and its conversion to the related anti and syn diol epoxide derivatives (32,33) has been reported (108). The isomeric trans-1,lOb-dihydrodiot 37) and the corresponding anti and syn diol epoxide isomers (38,39) have also been prepared (108) (Figure 19). Synthesis of 37 from 2,3-dihydro-fluoranthene (109) could not be accomplished by Prevost oxidation. An alternative route involving conversion of 2,3-dihydrofluoranthene to the i8-tetrahydrodiol (3-J) with OsO followed by dehydration, silylation, and oxidation with peracid gave the Ot-hydroxyketone 35. The trimethylsilyl ether derivative of the latter underwent stereoselective phenylselenylation to yield 36. Reduction of 3 with LiAlH, followed by oxidative elimination of the selenide function afforded 3J. Epoxidation of 37 with t-BuOOH/VO(acac) and de-silylation gave 38, while epoxidation of the acetate of JJ and deacetylation furnished 39. 

As students who first entered the Ecole Normale immediately after the war, in the same class of 1919, Kirrmann and Prevost became fast friends. They learned much from Lespieau, Dupont, and Bourguel, they developed similar theoretical views and practical methods, and they defended their doctoral dissertations on the same day in June 1928. It is to their work that we now turn. 

The dominant tendency of my studies has been not so much to obtain and describe organic compounds but... to penetrate their mechanisms.. . . For undertaking this kind of problem, the classic methods of organic chemistry are far from sufficient. Physicochemical procedures become more and more necessary. I have been led to use especially optical methods (the Raman effect and ultraviolet spectra) and electrochemical techniques (conductibility, electrode potentials, and especially polarography).. . . The notion of reaction mechanism led almost automatically to envisioning the electronic aspect of chemical phenomena. From 1927, and working in common with Charles Prevost, I have directed my attention on the electronic theory of reactions." 56... 

The joint memoirs of Prevost and Kirrmann self-consciously presented a general theory of organic chemistry that constituted an application of physical methods and principles to the problem of organic reaction mechanisms. However, the language system devised by Prevost and Kirrmann was not adopted by chemists in general, and that part of their notation which was new was not used outside France. Indeed, there was very little interest in their work inside France. 

Robert Lespieau s aim to establish a disciplinary specialization of "chemical theories" in France was partially realized in the work of some of his students, especially Dupont, Prevost, and Kirrmann. For the first time, a clearly defined research school in France practiced the art of "theoretical chemistry" in their study of organic structure and reaction mechanisms. They self-consciously employed physical methods and apparatus, and they stayed in contact with a small network of physicists who were teachers, friends of Lespieau, or immediate colleagues. They had a laboratory terrain that was the home meeting place, no matter what their current affiliation. They had a common history that could be traced back generation by generation in the Ecole Normale laboratory to Berthollet, the "father" of chemical mechanics. 

Lecoeur H, Ledru E, Prevost M-C, Gougeon M-L. 1997. Strategies for phenotyping apoptotic peripheral human lymphocytes comparing ISNT, annexin-V and 7-AAD cytofluorometric staining methods. J Immunol Methods 209 111-123. 

Only much later was the hydroxylation of pure trans-307 and cis-307 performed, and the corresponding ci.s-diols were obtained in 22-26% yield. The compound obtained from t ran 4-307 was converted199 into ert/fhro-pentopyranos-4-ulose hydrate by successive alkaline de-benzoylation, and hydrolysis of the acetal in the presence of Dowex W-50 resin. An attempt at direct tran.s--hydroxylation of trans-307 by Woodward s or Prevost s method failed, as have attempts at its epoxi-dation with peroxy acids.200 Nevertheless, a number of 3,4-epoxides... 

The same result can be achieved in one step with m-chloroperoxybenzoic acid and water.719 Overall anti addition can also be achieved by the method of Prevost. In this method the olefin is treated with iodine and silver benzoate in a 1 2 molar ratio. The initial addition is anti and results in a 3-halo benzoate (71). These can be isolated, and this represents a method of addition of IOCOPh. However, under the normal reaction conditions, the iodine is replaced by a second PhCOO group. This is a nucleophilic substitution reaction, and it operates by the neighboring-group mechanism (p. 308), so the groups are still anti ... 

Rousseaux, J., Rousseaux-Prevost, R., and Bazin, H. (1983) Optimal conditions for the preparation of Fab and F(ab )2 fragments from monoclonal IgG of different rat IgG subclasses. /. Immunol. Methods 64,141—146. 

Methyla-arylacetates. These esters have been obtained by oxidative rearrangement of alkyl aryl ketones with thallium(III) nitrate in acidic methanol or trimethyl orthoformate (4,496 5, 656 7, 362). A new method, which avoids the toxic TTN, is based on the Woodward version of the Prevost reaction. Thus, treatment of the ketone with iodine (or bromine) and silver nitrate (2 equiv.) in refluxing methanol containing trimethyl orthoformate results in methyl a-arylacetates in 90% yield from simple substrates. Yields are lowered by electron-withdrawing substituents on the aromatic group and by a-branching in the alkyl group.2... 

The practical application of the optical method of measuring temperature is made possible by the fact that the radiation from most solid bodies at high temperatures corresponds very closely to that from a perfect black body. In many metallurgical processes the temperature of a mass of material in a furnace has to be measured, and here the blackness of the radiation is still more perfect, as the furnace acts to a certain extent like a Prevost chamber. 

Heating stilbene with benzoyl peroxide and iodine in carbon tetrachloride at 80 °C for 48 h gives an 83% yield of the dibenzoyl ester of hydrobenzoin (l,2-dibenzoxy-l,2-diphenylethane) [230]. Esters of vicinal diols are intermediates in the preparation of diols by the Prevost and the Woodward methods (equation 78). 

Woodward method The syn-hydroxylation of an alkene the first step involves treating the alkene with iodine and silver acetate in a 1 1 molar ratio in wet acetic acid. The hydrolysis of the intermediate c/////-P-halogenoester is via a normal SN2 reaction in which there is no neighbouring group effect because the ester function is solvated by the water. Overall //-addition may be achieved by the method of Prevost. 

Silver salts of other acids have been employed in the Prevost reaction, as summarized by Wilson. As a means of preparing frani-glycols, the method seems to us less convenient and more costly than reaction with performic acid and hydrolysis. The presence of free iodine may lead to complications. A methoxybenzene with an olefinic side chain gave a glycol having an iodine substituent para to the methoxyl group. ... 

The modified Prevost reaction uses bismuth acetate instead of silver benzoate. From a mechanistic point of view, iodine is considered to be the actual oxidant, and hence the bismuth acetate may work merely as the acetoxy source. Major advantages of this method over the previously reported analogous ones are as follows (i) bismuth-containing wastes are non-toxic, (ii) bismuth acetate is inexpensive, and (iii) less metal salt is needed, since three acetoxyl groups can be transferred per one bismuth atom. 

Fayad PB, Prevost M, Sauve S, Laser diode thermal desorption/atmospheric pressure chemical ionization tandem mass spectrometry analysis of selected steroid hormones in wastewater Method optimization and application. Anal. Chem. 2010 82(2) 639-645. 

Prevost, J.H. 1977. Mathematical modelling of monotonic and cyclic undrained clay behavior. International Journal of Numerical and Analytical Methods in Geotechnical Engineering, 1, No. 2, pp. 195-216. 

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