Linked Life Data

12946148

Source:http://linkedlifedata.com/resource/pubmed/id/12946148

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2003-8-29
pubmed:abstractText
For dephosphorylation of bis(2,4-dinitrophenyl) phosphate (BDNPP) by hydroxylamine in water, pH region 4-12, the observed first-order rate constant, k(obs), initially increases as a function of pH, but is pH-independent between pH 7.2 and pH 10. The initial BDNPP cleavage by nonionic NH(2)OH (<0.2 M) involves attack by the OH group and follows first-order kinetics, but the overall initial reaction of BDNPP liberates ca. 1.7 mol of 2,4-dinitrophenoxide ion (DNP). This initial reaction generates a short-lived O-phosphorylated hydroxylamine, 2, followed by three possible reactions: (1) reaction of 2 with hydroxylamine, generating 2,4-dinitrophenyl phosphate (DNPP, 3), which subsequently forms DNP; (2) intramolecular displacement of the second DNP group and rapid decomposition of the cyclic intermediate to form phosphonohydroxylamine and eventually inorganic phosphate; (3) a novel rearrangement with intramolecular aromatic nucleophilic substitution involving a cyclic intermediate and migration of the 2,4-dinitrophenyl group from O to N. Values of k(obs) increase modestly with pH > 10, the reaction is biphasic, and the yield of DNP increases. An increase in [NH(2)OH] also increases the yield of DNP, due largely to accelerated hydrolysis of DNPP.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Sep
pubmed:issn
0022-3263
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7051-8
pubmed:year
2003
pubmed:articleTitle
Reactions of bis(2,4-dinitrophenyl) phosphate with hydroxylamine.
pubmed:affiliation
Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900, Brazil.
pubmed:publicationType
Journal Article