Issue 4, 2007

An investigation of the reduction in aqueous acetonitrile of 4-methoxybenzenediazonium ion by the tetrakis(acetonitrile)Cu(i) cation catalysed by hydrogenphosphate dianion

Abstract

In aqueous acetonitrile containing a phosphate buffer, 4-methoxybenzenediazonium ion is reduced by one or more of the partially aquated cations derived from tetrakis(acetonitrile)Cu(I) cation in this medium. Investigation of the reaction mechanism indicates the rate determining step to be the association of the diazonium ion with the hydrogenphosphate dianion to give an adduct which then undergoes reduction by Cu(I). The reaction gives a range of products which have been identified and quantified by GC. One of these, 4-methoxyphenol was unexpected in the reducing conditions; its presence could be explained by the disproportionation of a 4-methoxyphenylcopper(II) complex giving bis(4-methoxyphenyl)copper(III) which reacts with water to produce the phenol and an equivalent amount of methoxybenzene. A scheme is proposed which accounts for all the observed products and computer modelling gives a satisfactory description of the distributions of the five major products as functions of the relative proportions of the reactants for dilute conditions and those where the reductant is in excess. When the diazonium ion is in excess, the behaviour of the model and the experimental reactant accountability suggest the occurrence of additional reactions which give products unobserved by GC.

Graphical abstract: An investigation of the reduction in aqueous acetonitrile of 4-methoxybenzenediazonium ion by the tetrakis(acetonitrile)Cu(i) cation catalysed by hydrogenphosphate dianion

Supplementary files

Article information

Article type
Paper
Submitted
18 Oct 2006
Accepted
08 Dec 2006
First published
15 Jan 2007

Org. Biomol. Chem., 2007,5, 679-698

An investigation of the reduction in aqueous acetonitrile of 4-methoxybenzenediazonium ion by the tetrakis(acetonitrile)Cu(I) cation catalysed by hydrogenphosphate dianion

P. Hanson, A. B. Taylor, P. H. Walton and A. W. Timms, Org. Biomol. Chem., 2007, 5, 679 DOI: 10.1039/B615211B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements