Efficient reduction of aromatic nitro compounds catalyzed by nickel chloride supported on natural phosphate

Abstract

<jats:p>Natural phosphates are an important natural resource in Morocco, which need to be valorized; they can be used not only as primary raw material to produce the fertilizers but also as catalysts. In this work, we have prepared natural phosphate-supported nickel chloride (NiCl2/NP). This material was effectively used as a heterogeneous catalyst in the presence of sodium borohydride as a reducing agent. The reaction was carried out at room temperature in an aqueous medium. The catalyst showed an excellent activity for the reduction of aromatic nitro compounds under simple conditions along with good usability.</jats:p>

Ni/Pd-catalyzed Suzuki–Miyaura cross-coupling of alcohols and aldehydes and C–N cross-coupling of nitro and aminesviadomino redox reactions: base-free, hydride acceptor-free

“…Subsequently, a possible mechanism for the reduction of nitro compounds to amine and subsequent C-N coupling was proposed in accordance with the observations obtained from the control experiments and the reported mechanisms (Scheme 6). 30,31 According to this mechanism, NaBH 4 and the nitro groups on the surface of the catalyst are coordinated/linked through the Ni and Pd centers, respectively, and in several steps of hydride transfer from the BH 4 groups to nitro (intermediates I, II, III, and IV), [30][31][32] are reduced to an arylamine. Due to the presence of NaBH 4 groups in the medium, the reduction of Pd(II) to Pd(0) seems probable (in the case of direct the coupling of arylamines with aryl halides, this process can also be performed by amine groups 33,34 ).…”

Molecular Characterization of Water-Soluble Brown Carbon Chromophores in Snowpack from Northern Xinjiang, China

“…However, the dominant source of snow nitrophenols in polluted urban versus clean remote areas is likely different, which needs to be investigated in future studies. The UV–vis spectrum of C 7 H 7 NO 3 has a strong absorption band at ∼268 nm, closely resembling the spectrum of 3-nitrobenzyl alcohol . Nitrobenzyl alcohol, which has much fewer reports compared to nitrophenols, has been tentatively identified in studies of BBOA and SOA from oxidation of benzyl alcohol .…”

“…The UV−vis spectrum of C 7 H 7 NO 3 has a strong absorption band at ∼268 nm, closely resembling the spectrum of 3-nitrobenzyl alcohol. 106 Nitrobenzyl alcohol, which has much fewer reports compared to nitrophenols, has been tentatively identified in studies of BBOA 107 and SOA from oxidation of benzyl alcohol. 108 Other CHON chromophores are distinctively observed in urban samples, such as C 6 H 4 N 2 O 5 (#62, both samples U1 and U2), which has a similar UV−vis spectrum to 2,4-dinitrophenol.…”

Efficient reduction of nitro compounds and domino preparation of 1-substituted-1H-1,2,3,4-tetrazoles by Pd(ii)-polysalophen coated magnetite NPs as a robust versatile nanocomposite

“…The presence of water and NaBH 4 at each step causes the effective transfer of hydride to the nitro compound and the removal of the produced hydroxyl group as a water molecule. [51][52][53] In order to conrm the proposed mechanism, the catalyst surface charge was recorded by zeta potential analysis at 15, 30 and 45 minutes and also at the end of the nitrobenzene reduction reaction. Fig.…”