Umsetzung von Nitroaromaten mit Natriumborhydrid

Severin, Theodor; Schmitz, Reinold

doi:10.1002/cber.19620950616

Cited by 31 publications

(22 citation statements)

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“…2H Ϫ -TNP and H Ϫ -DNP were prepared according to the method of Severin et al (22,23) and stored at Ϫ20°C. All chemicals used were of the highest available purity and were purchased from Fluka (Taufkirchen, Germany), Merck, Roth (Karlsruhe, Germany), and Sigma-Aldrich (Taufkirchen, Germany).…”

Section: Methodsmentioning

confidence: 99%

“…As the trisodium salt of chemically synthesized 2H Ϫ -TNP is dissolved in buffer, the complex is instantaneously protonated to the aci-nitro form, which then slowly isomerizes to the nitro form (22,23). When the solution was allowed to stand at room temperature, the time needed to reach the equilibration ratio of 20:80 (aci-nitro-nitro form) was approximately 1 h at pH 7 whereas in the presence of NpdH it took approximately 0.1 min.…”

Section: Enzymatic Proton-shift Tautomerization Of 2hmentioning

confidence: 99%

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Nitrite Elimination and Hydrolytic Ring Cleavage in 2,4,6-Trinitrophenol (Picric Acid) Degradation

Hofmann

Knackmuss

Heiss

2004

Appl Environ Microbiol

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Two hydrogenation reactions in the initial steps of degradation of 2,4,6-trinitrophenol produce the dihydride Meisenheimer complex of 2,4,6-trinitrophenol. The npdH gene (contained in the npd gene cluster of the 2,4,6-trinitrophenol-degrading strain Rhodococcus opacus HL PM-1) was shown here to encode a tautomerase, catalyzing a proton shift between the aci-nitro and the nitro forms of the dihydride Meisenheimer complex of 2,4,6-trinitrophenol. An enzyme (which eliminated nitrite from the aci-nitro form but not the nitro form of the dihydride complex of 2,4,6-trinitrophenol) was purified from the 2,4,6-trinitrophenol-degrading strain Nocardioides simplex FJ2-1A. The product of nitrite release was the hydride Meisenheimer complex of 2,4-dinitrophenol, which was hydrogenated to the dihydride Meisenheimer complex of 2,4-dinitrophenol by the hydride transferase I and the NADPH-dependent F 420 reductase from strain HL PM-1. At pH 7.5, the dihydride complex of 2,4-dinitrophenol is protonated to 2,4-dinitrocyclohexanone. A hydrolase was purified from strain FJ2-1A and shown to cleave 2,4-dinitrocyclohexanone hydrolytically to 4,6-dinitrohexanoate.2,4,6-Trinitrophenol (TNP) and 2,4-dinitrophenol (DNP) are nitroaromatic compounds of versatile use in chemical synthesis. They occur as off-stream chemicals during the production of aniline, which is one of the most important starting materials in chemical synthesis. Furthermore, TNP and its salts have been used as explosives. Large quantities of TNP in waste streams of aniline production necessitate remediation. Several bacteria of the Actinomycetales family (notably of the genera Rhodococcus and Nocardioides) grow aerobically on TNP and/or DNP and utilize the compounds as sole nitrogen, carbon, and energy sources (3,4,10,19). This capacity can be harnessed for bioremediation once we understand the underlying mechanisms of these processes.It was previously established that two hydrogenations take place in the initial attack on TNP (6,7,8,11) (Fig. 1A, panel 1). In Rhodococcus opacus HL PM-1, TNP is hydrogenated at the aromatic nucleus by the hydride transferase II (HTII) encoded by npdI (Fig. 1B) and the NADPH-dependent F 420 reductase (NDFR) encoded by npdG. The hydride Meisenheimer complex of TNP (H Ϫ -TNP) (Fig. 1A, panel 2) thereby formed is further hydrogenated by the hydride transferase I (HTI) encoded by npdC and the NDFR, producing the dihydride Meisenheimer complex of TNP (2H Ϫ -TNP) (panel 3a). In Nocardioides simplex FJ2-1A, the same reactions take place except that a single hydride transferase performs both hydrogenations (7).More than a decade ago, 4,6-dinitrohexanoate was identified as a dead-end metabolite of TNP degradation resulting from two hydride transfers to TNP. This observation coincided with the hypothesis that 2HϪ -TNP was a dead-end metabolite of TNP degradation (11). Much later it was suggested that nitrite is eliminated from 2H Ϫ -TNP to produce the hydride Meisen-Ϫ -TNP is a metabolite of productive TNP degradation. Detection of H Ϫ -DNP suggest...

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Section: Methodsmentioning

confidence: 99%

Section: Enzymatic Proton-shift Tautomerization Of 2hmentioning

confidence: 99%

Nitrite Elimination and Hydrolytic Ring Cleavage in 2,4,6-Trinitrophenol (Picric Acid) Degradation

Hofmann

Knackmuss

Heiss

2004

Appl Environ Microbiol

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“…The precipitating dark powdery crystals were filtered through a sintered glass filter, followed by washing with ice-cold, absolute acetonitrile and finally dried in a vacuum (Christ Alpha I-5). 2H − -PA was prepared according to Severin & Schmitz (1962).…”

Section: Methodsmentioning

confidence: 99%

npd gene functions of Rhodococcus (opacus) erythropolis HL PM-1 in the initial steps of 2,4,6-trinitrophenol degradation b bThe GenBank accession number for the sequence reported in this paper is AF435009.

et al. 2002

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“…Pentaoxorhenates of the type Me:ReO5 or My(ReOS)2 were obtained with Na and K as Me1 and Ba and Sr as MeTI. Na3ReOS and K3ReO5 are isotypes of the corresponding osmates(VI1) [4]; furthermore, the compound K3105, which is isotypic with K3Re05, was prepared for the first time. There are two modifications of Ba3(Re05)2.…”

Section: Institut Fur Anorganische Chemie Der Technischen Hochschule mentioning

confidence: 99%

“…Compound (2) was not isolated but its structure is assured from our previous investigations on reactions of nitroaromatic compounds and sodium borohydride [4] o n the one hand, and by the action of bromine on (2), which leads to reoxydation of the nucleus, removal of a nitro group, and ring closure to give 4,6-dinitro-2-methylcoumaran (3) on the other; the yield was 35 %, based on (2).…”

Section: -248 "C Prepared Frommentioning

confidence: 99%

Hexabenzooctalene from Tribenzotropone

Tochtermann¹

1963

Angew. Chem. Int. Ed. Engl.

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Alkali and alkaline-earth oxorhenates(VI1) and oxorhenates-(VI) were prepared by thermal reaction of appropriate miutures in the solid phase. They were unequivocally differentiated by quantitative analysis, X-ray analyses (as far as possible by determination of the lattice parameters), and in some cases by determination of their solubilities in absolute methanol. In addition to tetraoxorhenates(VI1) of the type MeIRe04 and Mer1(Re0& (Me = metal cation), penta-and hexaoxorhenates containing Rev11 were prepared by thermal reaction of the corresponding tetraoxorhenate(VI1) with oxides or carbonates of Li, Na, Ba, Sr, or Ca; in order to obtain K3Re05, KOH was used as the basic component. Pentaoxorhenates of the type Me:ReO5 or My(ReOS)2 were obtained with Na and K as Me1 and Ba and Sr as MeTI. Na3ReOSand K3ReO5 are isotypes of the corresponding osmates(VI1) [4]; furthermore, the compound K3105, which is isotypic with K3Re05, was prepared for the first time. There are two modifications of Ba3(Re05)2. Hexaoxorhenates of the type Me: Re06 or Mey(Re06)2 (Me1 = Li, Na; Me11 = Ba, Sr, Ca) are isotypic with the corresponding osmates(VI1) 141 and iodates(VI1). Li5ReO6 was assigned to the hexagonal system (lattice constants: a0 = 5.053 A, co = 14.21 A, cia = 2.81).The yellow to orange color of oxorhenates(VI1) with higher oxygen co-ordinztion is noteworthy, in contrast to the tetraoxorhenates, which are colorless; they are split immediately by water into tetraoxorhenates(VI1) and free base. Rhenates containing Rev1 are obtained by interaction of oxorhenates(VII), metallic Re, and the appropriate quantity of a basic oxide. In the system LizO-ReO3, the compounds Li4ReOs and &Re06 both exist in two modifications. The low-temperature form of Li4ReO5 has the Lang structure [51 and probably has the formula Li~[Re0.&i0.4]03, while a-Li4ReOs is isotypic with Li4WO5 [6] and Li4TeO5 171. The fact that P-LisReOs and Li~Re06 are clearly isotypes is worthy of note (lattice constants of P-Lis~eOs: a0 = 5.03 A, co = 14.12 A, c/a = 2.81). The compound Li4MgReO6 was also prepared for the first time and has the same type of structure. Li6oso6 [S] crystallizes in a similar lattice. cc-Li6ReO6 is isotypic with Li6wo6 161; it cannot be indexed from its powder diagram. Received, March 13th, 1963 [Z 466/295 IEI In the ternary system Me-Re-0, there are compounds with the orderedperovskitestructure and thecomposition Me3Re06 (Me = Ba, Sr, Ca) 131. However, of these only Ba3ReO6, which was obtained in two tetragonal modifications, could be indexed from a powder diagram. Of the compounds of the type Me'Me"ReO6, all the combinations with Me' = Ba, Sr, or Ca and Me" = Ba, Sr, Ca, or Mg wcre prepared (partly in agreement with the results of Ward [41); all the compounds possess the ordered perovskite structure. Furthermore, a rhombohedral phase Ba3ReO,j-0.3BaO was obtained pure. Compounds ofthe type MeSRezOli (Me = Sr or Ca) also possess the perovskite structure. The new compounds BaZReOS (isotypic with BazX05, X = Te, Mo, W, or 0 s ) [ 5 ] and SrzReOs...

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Umsetzung von Nitroaromaten mit Natriumborhydrid

Abstract: Einige Polynitroaromaten lassen sich mit Natriumborhydrid in guter Ausbeute zu den entsprechenden Nitrocyclohexanen bzw. Nitrocyclohexenen umsetzen.

Cited by 31 publications

References 2 publications

Nitrite Elimination and Hydrolytic Ring Cleavage in 2,4,6-Trinitrophenol (Picric Acid) Degradation

Nitrite Elimination and Hydrolytic Ring Cleavage in 2,4,6-Trinitrophenol (Picric Acid) Degradation

npd gene functions of Rhodococcus (opacus) erythropolis HL PM-1 in the initial steps of 2,4,6-trinitrophenol degradation b bThe GenBank accession number for the sequence reported in this paper is AF435009.

Hexabenzooctalene from Tribenzotropone

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