Sodium periodate tetroxide

Chemical degradation studies carried out on streptovaricias A and C, which are the primary components of the cmde complex, yielded substances shown ia Figure 1. Streptovaricia A (4), consumes two moles of sodium periodate to yield variciaal A [21913-68-8] (1), 0 2 200, which accounts for the ahphatic portion of the molecule, and prestreptovarone [58074-37-6] (2), C2C)H2C)N02, which accounts for the aromatic chromophore of the streptovaricias (Fig. 2). Streptovaricia G (9) is the only other streptovaricia that yields prestreptovaroae upoa treatmeat with sodium periodate. Treatmeat of streptovaricias A (4), B (5), C (6), E (8), and G (9) with sodium periodate and osmium tetroxide yields streptovarone [36108-44-8] (3), C24H23NO2, which is also produced by the reaction of prestreptovarone with sodium periodate and osmium tetroxide (4,65). A number of aliphatic products were isolated from the oxidation of streptovaricia C and its derivatives (66). 

Osmium tetroxide used in combination with sodium periodate can also effect alkene cleavage.191 Successful oxidative cleavage of double bonds using ruthenium tetroxide and sodium periodate has also been reported.192 In these procedures the osmium or ruthenium can be used in substoichiometric amounts because the periodate reoxidizes the metal to the tetroxide state. Entries 1 to 4 in Scheme 12.18 are examples of these procedures. Entries 5 and 6 show reactions carried out in the course of multistep syntheses. The reaction in Entry 5 followed a 5-exo radical cyclization and served to excise an extraneous carbon. The reaction in Entry 6 followed introduction of the allyl group by enolate alkylation. The aldehyde group in the product was used to introduce an amino group by reductive alkylation (see Section 5.3.1.2). 

In summary, the reaction of osmium tetroxide with alkenes is a reliable and selective transformation. Chiral diamines and cinchona alkakoid are most frequently used as chiral auxiliaries. Complexes derived from osmium tetroxide with diamines do not undergo catalytic turnover, whereas dihydroquinidine and dihydroquinine derivatives have been found to be very effective catalysts for the oxidation of a variety of alkenes. OsC>4 can be used catalytically in the presence of a secondary oxygen donor (e.g., H202, TBHP, A -methylmorpholine-/V-oxide, sodium periodate, 02, sodium hypochlorite, potassium ferricyanide). Furthermore, a remarkable rate enhancement occurs with the addition of a nucleophilic ligand such as pyridine or a tertiary amine. Table 4-11 lists the preferred chiral ligands for the dihydroxylation of a variety of olefins.61 Table 4-12 lists the recommended ligands for each class of olefins. 

Osmium tetroxide used in combination with sodium periodate can also effect alkene cleavage.135 Successful oxidative cleavage of double bonds using ruthenium tetroxide and sodium periodate has also been reported.136 In these procedures, the osmium or ruthenium can be used in substoichiometric amounts because the periodate reoxidizes the metal to the tetroxide state. Entries 1 4 in Scheme 12.17 are examples of these procedures. 

Exposure of 144 to catalytic quantities of ruthenium tetroxide, generated in situ from ruthenium trichloride and sodium periodate, produces the symmetrical lactones 145 <2000JA9558>. It is proposed that the products form as a result of the ruthenium-catalyzed oxidative cleavage of the a-diketones to produce intermediate glycols (Equation 49). 

Treatment of 53 with DAST [(diethylamino)sulfur trifluoride] in methylene chloride provided 57 in 50% yield. Compound 57 was treated with osmium tetroxide at 5 °C in the presence of NMO (4-methylmopholine N-oxide) for 18 h to provide 58 and 59, which were separated by silica-gel chromatography. Compounds 58 and 59 were treated with sodium periodate at 5 °C for 18 h to provide 60 and 61 respectively. Compounds 60 and 61 were treated with CDsMgl followed by NaB CN to give 62 in 20% and 50% yields, respectively. 

Ruthenium(IV) oxide-Sodium periodate, 268 Ruthenium tetroxide, 268 Tetrachlorotris [ bis (1,4-diphenylphos-phine)butane]diruthenium, 288 Tetrakis(trifluoroacetate)ruthenium, 289... 

Exercise 16-37 An elegant modification of the two-step procedure to prepare ketones from alkenes by hydroxylation and oxidative cleavage of the diol formed uses a small amount of potassium permanganate (or osmium tetroxide, 0s04) as the catalyst and sodium periodate as the oxidizing agent ... 

In a first step, the TBS ether is subjected to acid cleavage with copper sulfate in acetone containing a catalytic amount of glacial acetic acid. The resulting diol is then protected as an acetunide. Next, the double bond is oxidatively cleaved with sodium periodate and a catalytic amount of osmium tetroxide to give aldehyde 5. 

The use of cyclic sulfates in synthetic applications has been limited in the past because, although cyclic sulfites are easily prepared from diols, a convenient method for oxidation of the cyclic sulfites to cyclic sulfates had not been developed. The experiments of Denmark [70] and of Lowe and co-workers [71 ] with stoichiometric ruthenium tetroxide oxidations and of Brandes and Katzenellenbogen [72a] and Gao and Sharpless [68] with catalytic ruthenium tetroxide and sodium periodate as cooxidant have led to an efficient method for this oxidation step. Examples of the conversion of several diols (67) to cyclic sulfites (68) followed by oxidation to cyclic sulfates (69) are listed in Table 6D.7. The cyclic sulfite/cyclic sulfate sequence has been applied to 1,2-, 1,3-, and 1,4-diols with equal success. Cyclic sulfates, like epoxides, are excellent electrophiles and, as a consequence of their stereoelectronic makeup, are less susceptible to the elimination reactions that usually accompany attack by nucleophiles at a secondary carbon. With the development of convenient methods for their syntheses, the reactions of cyclic sulfates have been explored, Most of the reactions have been nucleophilic displacements with opening of the cyclic sulfate ring. The variety of nucleophiles used in this way is already extensive and includes H [68], [68,73-76], F" [68,72,74], PhCOCT [68,73,74], NOJ [68], SCN [68],... 

The most widely used method for the preparation of 1,3,2-dioxathiolane. Y-oxides (cyclic sulfites) 65 bearing C-linked substituents is the reaction of the corresponding 1,2-diols with thionyl chloride in presence of pyridine or Et3N (Scheme 18). More reactive 1,3,2-dioxathiolane. Y,.Y-dioxidcs (cyclic sulfates) 66 are usually obtained by oxidation of sulfites 65 with sodium periodate, which is mediated by mthenium tetroxide generated in situ from a catalytic amount of ruthenium trichloride. Numerous derivatives 65 and 66 were obtained via this approach and its modifications for further transformations, mostly as the synthetic equivalents of epoxides <1997AHC89, 2000T7051> (see also Sections 6.05.5 and 6.05.6, and Tables 1-7). 

Pc with osmium tetroxide and sodium periodate, and subsequent 1,3-dipolar cycloaddition of the azomethine ylide, formed in the presence of an excess of sarco-sine, and Cgo to give the fulleropyrrolidine-Pc conjugate 17. The second protocol relies on the fulleropyrrolidine formation prior to the statistical cyclotetrameriza-tion with 4-tert-bu tv I p It lit a lonitrile. The low yields obtained via the latter strategy are presumably a result of the steric congestion of the benzodinitrile-functionalized fullerene precursor in the statistical crossover condensation. 

The rest of the synthesis (Scheme 13) is completely stereospecific and most of the steps are known (20). The bicyclic acid was oxidatively decarboxylated with lead tetraacetate and copper acetate (21). The resulting enone was alkylated with methyllithium giving a single crystalline allylic tertiary alcohol. This compound was cleaved with osmium tetroxide and sodium periodate. Inverse addition of the Wittig reagent effected methylenation in 85% yield. Finally, the acid was reduced with lithium aluminum hydride to grandisol. 

The Step 5 product (410 mg) dissolved in 15 ml THF and 5 ml water was treated with 1.1ml 2.5% solution osmium tetroxide in t-butyl alcohol followed by the portionwise addition of sodium periodate (686 mg), then stirred overnight at ambient temperature. The mixture was concentrated and the residue dissolved in 26 ml... 

The Step 7 product (113 mmol) dissolved in 600 ml dioxane was treated with 200 ml water and 4 ml 4% aqueous solution of osmium tetroxide, then stirred 5 minutes, and treated with sodium periodate (469 mmol). The mixture was heated 3 hours at 35°C, then cooled to ambient temperature, and diluted with 11 EtOAc. The solution was then washed with water, dried, and concentrated. The residue was recrystallized using THF and 15 g of product was isolated. The remaining filtrate was purified by chromatography with silica gel and EtOAc/hexanes, 1 1, so that a total product yield of 44% was observed. 

Sodium periodate, used along with catalytic amounts of osmium tetroxide, radienium dioxide or potassium permanganatt, can also be employed to cleave carbon-carbon double bonds. When used with osmium tetroxide, carbonyls are produced however, the presence of permanganate results in the formation of more highly oxidized products (carboxylic acids) finom secondary carbons. 

A mixture of ruthenium tetroxide, sodium periodate and sodium acetate was effective for the conversion shown in equation (49). ... 

Osmium tetroxide reacts with double bonds to form cyclic osmate(VI) diesters (10), which can then be hydrolyzed to provide vicinal diols in good yields. - iK however, sodium periodate is also present, the diol is cleaved, as in Scheme 2, and carbonyl compounds are the final products. Periodate serves the additional purpose of regenerating osmium tetroxide, thus permitting the use of this expensive and toxic reagent in minimum amounts. 

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