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Oxidative cleavage nitric acid

A 2-alkoxyethanol with a fluorine-containing alkoxy group can be selectively oxidized by nitric acid to the 2-alkoxyacetic acid without cleavage of the ether bond, e.g. oxidation of 9 to 10.148... [Pg.36]

Oxidations with nitric acid under the best conditions convert primary alcoholic and aldehydic groups to carboxylic groups. Frequently, however, cleavage of carbon-carbon bonds occurs. For galactose the conversion to insoluble mucic acid, COOH—(CHOH)4—COOH, takes place to an extent greater than 70 %, and the reaction is used for the quantitative determination of this sugar (229, 230). This oxidation has been halted before completion and a 10% yield of the L-galacturonic acid obtained (231). Smaller... [Pg.353]

The ester linkage of depsidones is easily hydrolyzed, as is the case with depsides, but cleavage of the ether linkage calls for more drastic means such as fusion with KOH or oxidation with nitric acid. [Pg.510]

Oxidation. Ketones are oxidized with powerful oxidizing agents such as chromic or nitric acid. During oxidation, carbon—carbon bond cleavage occurs to produce carboxyHc acids. Ketone oxidation with hydrogen peroxide, or prolonged exposure to air and heat, can produce peroxides. Concentrated solutions of ketone peroxides (>30%) may explode, but dilute solutions are useful in curing unsaturated polyester resin mixtures (see... [Pg.487]

Cleavage of an alkenoic acid can be carried out with permanganate, a permanganate—periodate mixture, periodate or with nitric acid, dichromate, ozone, or, if the unsaturation is first converted to a dihydroxy compound, lead tetraacetate (71,73). Oxidative ozonolysis is a process for the manufacture of azelaic acid [123-99-9] and pelargonic acid (74). [Pg.86]

Physical and Chemical Properties. The (F)- and (Z)-isomers of cinnamaldehyde are both known. (F)-Cinnamaldehyde [14371-10-9] is generally produced commercially and its properties are given in Table 2. Cinnamaldehyde undergoes reactions that are typical of an a,P-unsaturated aromatic aldehyde. Slow oxidation to cinnamic acid is observed upon exposure to air. This process can be accelerated in the presence of transition-metal catalysts such as cobalt acetate (28). Under more vigorous conditions with either nitric or chromic acid, cleavage at the double bond occurs to afford benzoic acid. Epoxidation of cinnamaldehyde via a conjugate addition mechanism is observed upon treatment with a salt of /-butyl hydroperoxide (29). [Pg.174]

A great number of transformations has been performed on narceine imide (116) by Czech researchers. Oxidation with potassium permanganate in acetone or with nitric acid caused the cleavage of the alkaloid, giving rise to hemipinic imide (127). A similar result was noted by Rdnsch (129,130) during Lemieux-Johnson oxidation of ene lactam 152 (129,130) in this reaction the basic component (156) was isolated as well. The use of hydrogen peroxide in acetone converted 116 to (Z)-narceine imide N-oxide, which under the action of acetic anhydride underwent N-dealkylation (135). [Pg.279]

The one-electron oxidation of iV-benzylphenothiazine by nitric acid occurs in the presence of /i-cyclodextrin, which stabilizes the radical cation by incorporation into its cavity. The reaction is inhibited by adamantane, which preferentially occupies the cavity. Novel Pummerer-type rearrangements of / -sulfinylphenyl derivatives, yielding /7-quinones and protected dihydroquinones, and highly enantioselective Pummerer-type rearrangements of chiral, non-racemic sulfoxides have been reviewed. A comprehensive study has demonstrated that the redox potential for 7- and 8-substituted flavins is linearly correlated with Hammett a values. DFT calculations in [3.3.n]pro-pellanes highlight low ionization potentials that favour SET oxidative cleavage of the strained central C-C bond rather than direct C-H or C-C bond attack. Oxidations and reductions in water have been reviewed. ... [Pg.245]

The choice of reagent determines whether a nitrosamine undergoes conversion to a nitramine by either nitrolysis or oxidation. An example is given for the conversion of 1,3,5-trinitroso-1,3,5-triazacyclohexane (109) to l,3,5-trinitro-l,3,5-triazacyclohexane (3) (RDX) - the use of 30 % hydrogen peroxide in 99 % nitric acid at subambient temperature goes via oxidation of the nitrosamine functionality, whereas dinitrogen pentoxide in pure nitric acid makes use of a nitrolysis pathway via C-N bond cleavage. [Pg.221]

Chemical Properties NG reacts chemically as a nitrate ester, saponifiable to glycerol by alka-lies (preferably with peroxide present), and hydrolyzed by nitric acid to glycerol. In general, side products tend (d be produced resulting from cleavage of the C—C bonds and oxidation of the alcohol functions... [Pg.741]

Eastham and Derwent474 have also studied the kinetics of the perchloric acid-catalyzed reaction of ethylene oxide with pyridine. In excess of pyridine the rate was found to be dependent on the Conor Titrations of ethylene oxide and perchloric add. Addition of stronger bases,. g. ammonia, triethylamine, or benzylamiae, depressed the vum of cleavage, presumably by competing with ethylene oxide for thr-available proton source, believed to be pyridinium perchlorate in this case. Other acids examined included nitric acid and hydroiodie irireaction rate depended to a certain extent... [Pg.169]

Oxidation of methylated sugars with nitric acid was used extensively by early workers for locating the position of unsubstituted hydroxyl groups.116 Cleavage of carbon-carbon bonds appears to be facilitated by the presence of such catalysts as vanadium salts. As hot nitric acid acts as a hydrolyzing agent as well as an oxidant, oligo- and poly-saccharides may be used directly. [Pg.341]


See other pages where Oxidative cleavage nitric acid is mentioned: [Pg.677]    [Pg.37]    [Pg.366]    [Pg.340]    [Pg.377]    [Pg.366]    [Pg.377]    [Pg.377]    [Pg.6511]    [Pg.296]    [Pg.669]    [Pg.762]    [Pg.243]    [Pg.269]    [Pg.1527]    [Pg.16]    [Pg.500]    [Pg.216]    [Pg.292]    [Pg.44]    [Pg.525]    [Pg.335]    [Pg.562]    [Pg.251]    [Pg.273]    [Pg.321]    [Pg.50]    [Pg.1183]    [Pg.503]    [Pg.589]    [Pg.1151]    [Pg.29]    [Pg.41]    [Pg.232]    [Pg.479]    [Pg.573]    [Pg.61]   
See also in sourсe #XX -- [ Pg.199 ]

See also in sourсe #XX -- [ Pg.199 ]




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Acidic cleavage

Cleavage acids

Nitric acid oxidation

Nitric acid, oxidizers

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