Metal-Catalyzed Hydroperoxide Reactions. I. Substituent Effects in the Oxidation of Aniline

Howe, G. R.; Hiatt, R.

doi:10.1021/jo00837a700

Cited by 67 publications

(20 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Interestingly, even at a potential of +0.8 V a conversion of about 80.4% with a selectivity of 91.8% nitrobenzene is observed when TBHP was used as the oxidant. The higher electrocatalytic conversion m presence of TBHP can be attributed to the favorable formation of an electron deficient transition state (t-bu +) during the heterolytic cleavage of TBHP [2] and the observed peroxide selectivity is 18 times higher in the case of TBHP when compared to H202. In the case of H202, since a free radical mechanism is believed to be operative, it is expected that the electrochemical control by the applied potential may not be crucial.…”

Section: Resultsmentioning

confidence: 99%

“…example, vanadium oxyacetylacetonate [2], sodium perborate [3], ozone [4] and peracetic acid [5] have been reported to be good reagents for the oxidation of anilines to nitrobenzenes. In addition, oxidation of various primary amines to the corresponding oximes and imines over vanadium silicate molecular sieves, VS-1 has also been reported [6].…”

Section: Introductionmentioning

confidence: 99%

“…Further, detailed studies regarding the oxidation of aniline to azoxybenzene over TS-1 using both H202 and TBHP have recently demonstrated several important mechanistic features [7]. Since vanadium oxyacetylacetonate [2] and TBHP are reported to convert anilines to nitrobenzenes in homogeneous condition, it is important to correlate the common features associated with the same process using vanadium silicate molecular sieves (VS-1), albeit under heterogeneous conditions. Although, the conversion of aniline to nitrobenzene has no immediate practical utility because aniline itself is prepared by reduction of nitrobenzene, an understanding of the mechanism of conversion of aniline to nitrobenzene using VS-1 will be important to decide the role of vanadium redox transformations especially in restricted environments.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Catalytic and electrocatalytic oxidation of aniline to nitrobenzene over vanadium silicate molecular sieves: VS-1 usingt-butyl hydroperoxide (TBHP) as oxidant

Selyam

Vinod

Vijayamohanan

1997

React Kinet Catal Lett

View full text Add to dashboard Cite

A comparison of the results of catalytic and electrocatalytic oxidation of aniline using VS-1 in the presence of 1-1202 and TBHP indicates remarkable differences in conversion and selectivity. VS-1 catalyzes the oxidation of aniline selectively to nitrobenzene (73%) in the presence of t-butyl hydroperoxide (TBHP), while azoxybenzene (95.2%) is formed selectively when H202 is used. Cyclic voltammetrie studies show a three-step oxidation of aniline to nitrobenzene in H202 but in the presence of TBHP only one step is observed. Electrocatalytic oxidation of aniline to nitrobenzene occurs at a potential 700 mV less than that corresponding to H~.O2 as oxidant along with a selectivity of 91.8%. The enhancement of e, lectrocatalytic rate is attributed to the stabilization of electron deficient transition state.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Catalytic and electrocatalytic oxidation of aniline to nitrobenzene over vanadium silicate molecular sieves: VS-1 usingt-butyl hydroperoxide (TBHP) as oxidant

Selyam

Vinod

Vijayamohanan

1997

React Kinet Catal Lett

View full text Add to dashboard Cite

show abstract

“…For example, when such amines are oxidized, one would obtain a variety of higher oxygenated products such as hydroxylamine, nitroso compound, or oxime. Although there are many reports of such oxidations available in the literature, [30][31][32][33][34][35][36][37][38][39] the existing methods suffer from low yields of oximes.…”

Section: Oxidation Of N-h Bonds Of Organic Aminesmentioning

confidence: 99%

A Novel Synthesis and Characterization of Titanium Superoxide and its Application in Organic Oxidative Processes

et al. 2010

View full text Add to dashboard Cite

A novel, exceptionally stable titanium superoxide radical ion was prepared and its structure determined by FTIR, ESR, Raman spectroscopy, X-ray diffraction, thermogravimetric/differential thermal analysis and elemental analysis. This heterogeneous catalyst has been found to be effective for the selective oxidation of aromatic amines and phenols to the corresponding nitro aromatics and p-quinones, respectively. In addition, this non-toxic, inexpensive and reusable catalyst has also been used in aminobromination of olefins, which proceed to give the 1, 2-bromoaminated anti-Markovnikov product. A brief account of these results is summarized in this review.

show abstract

“…Dimeric products such as azo-or azoxy-derivatives 9,13a as well as over-oxidation to the nitro compounds 7,10,11 were often observed as by-products or sometimes as main products. 6,14 Some methods for the direct oxidation of aromatic amines to nitro derivatives were described with peracids, 15 and more recently with dioxirane, 16 tert-butyl peroxide or H 2 O 2 as oxidants and metal peroxocomplexes (Mo, 17 W, 6,10,11 V, 17 Zr, 12 Re 18 ) or with chromium silicalit 13 as catalyst.…”

mentioning

confidence: 99%

Simple Preparation of Nitroso Benzenes and Nitro Benzenes by Oxidation of Anilines with H₂O₂Catalysed with Molybdenum Salts

Defoin¹

2004

Synthesis

View full text Add to dashboard Cite

Nitroso arenes 2a-k are prepared in 53-80% yield from anilines 1a-k by oxidation with H 2 O 2 catalysed with MoO 3 /KOH, ammonium molybdate or other molybdenum salts. Further oxidation to nitro arenes 3a,d,j in 66-90% is also described.Classic methods for the preparation of aromatic nitroso compounds are oxidation of anilines with peracids, 1 particularly Caro acid, 2 peracetic acid, 1 perbenzoic acid, 3,4 trifluoroperacetic acid 5 or more recently molybdic peroxo-complexes. 6 Catalytic methods using H 2 O 2 or tertbutyl peroxide as oxidant and sodium tungstate, 7 oxomolybdate complexes, 8 phosphotungstate, 9-11 phosphomolybdate 10,11 or zirconate salts 12 were published later. Dimeric products such as azo-or azoxy-derivatives 9,13a as well as over-oxidation to the nitro compounds 7,10,11 were often observed as by-products or sometimes as main products. 6,14 Some methods for the direct oxidation of aromatic amines to nitro derivatives were described with peracids, 15 and more recently with dioxirane, 16 tert-butyl peroxide or H 2 O 2 as oxidants and metal peroxocomplexes (Mo, 17 W, 6,10,11 V, 17 Zr, 12 Re 18 ) or with chromium silicalit 13 as catalyst.We describe herein a simple oxidation method of anilines, resulting in the corresponding nitroso compounds using 30% H 2 O 2 and molybdenum trioxide or other molybdenum salts as catalyst without the formation of azo-or azoxy-derivatives. Further oxidation to nitro compounds was examined in some cases. Oxidation of Anilines to Nitroso ArenesOxidation of anilines 1a-k was carried out in a watermethanol solution in which the anilines were only slightly soluble but the resulting nitroso compounds 2a-g,j,k were insoluble and could be isolated by filtration (Scheme 1). Side-reactions such as formation of nitro derivatives and dimeric compounds such as azo-or azoxy-derivatives was also minimised. This method appeared to be better than the previous two-phase preparation. 4,8,9,11 A complete oxidation and a sufficient reaction rate required an excess of H 2 O 2 (4 equiv) and 0.1 mol of molybdic derivative per 1 mol of aniline, smaller proportions of oxidant or catalyst led to slower or incomplete reactions and favoured the formation of azo-azoxy-or coloured-compounds. Scheme 1 a) Dependence on the pH-Valuep-Chloroaniline 1a was used as the model compound and the standard catalyst was 10 mol% MoO 3 in the presence of KOH as the base, which was added in various quantities. Oxidation of p-chloroaniline is very dependent on MoO 3 /KOH molar ratio. The results are listed in Table 1, and summarised here.-With MoO 3 only without added base, the oxidation occurred cleanly, but the progress of the reaction was slow (15% reaction after 1 d).-With MoO 3 and 1-1.8 equiv KOH, the oxidation rate increased with the concentration of base, but coloured impurities were formed when 1.5-1.8 equiv of base (pH value 5-7) were added. The best condition for the oxidation to the nitroso compound was with 1-1.2 equiv KOH, then the oxidation occurred cleanly and gave good yields (86-94%) of the nitro...

show abstract

Metal-Catalyzed Hydroperoxide Reactions. I. Substituent Effects in the Oxidation of Aniline

Cited by 67 publications

References 3 publications

Catalytic and electrocatalytic oxidation of aniline to nitrobenzene over vanadium silicate molecular sieves: VS-1 usingt-butyl hydroperoxide (TBHP) as oxidant

Catalytic and electrocatalytic oxidation of aniline to nitrobenzene over vanadium silicate molecular sieves: VS-1 usingt-butyl hydroperoxide (TBHP) as oxidant

A Novel Synthesis and Characterization of Titanium Superoxide and its Application in Organic Oxidative Processes

Simple Preparation of Nitroso Benzenes and Nitro Benzenes by Oxidation of Anilines with H₂O₂Catalysed with Molybdenum Salts

Contact Info

Product

Resources

About

Metal-Catalyzed Hydroperoxide Reactions. I. Substituent Effects in the Oxidation of Aniline

Cited by 67 publications

References 3 publications

Catalytic and electrocatalytic oxidation of aniline to nitrobenzene over vanadium silicate molecular sieves: VS-1 usingt-butyl hydroperoxide (TBHP) as oxidant

Catalytic and electrocatalytic oxidation of aniline to nitrobenzene over vanadium silicate molecular sieves: VS-1 usingt-butyl hydroperoxide (TBHP) as oxidant

A Novel Synthesis and Characterization of Titanium Superoxide and its Application in Organic Oxidative Processes

Simple Preparation of Nitroso Benzenes and Nitro Benzenes by Oxidation of Anilines with H2O2Catalysed with Molybdenum Salts

Contact Info

Product

Resources

About

Simple Preparation of Nitroso Benzenes and Nitro Benzenes by Oxidation of Anilines with H₂O₂Catalysed with Molybdenum Salts