Sargeson and coworkers

The early work of the group is dealt with in a review which 

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In 1984 Sargeson and coworkers [31] have detected that the dinuclear, p-nitrophenyl phosphate-bridged cobalt(III) complex 1 rapidly hydrolyzes in water at pH 10 and 25 °C (k = 2 x 10 2 s-1). Based on a detailed kinetic investigation the authors suggest intramolecular attack of coor-... 

The first cobalt(II) and cobalt(III) Se-sarcophaginates were obtained by Sargeson and coworkers [146] from the preliminarily synthesized free diMEsar-Se ligand (Scheme 65). 

Attempts of Sargeson and coworkers [158] to cross-link the chromium(III) tris-ethylenediaminate have not been successful because of rapid dissociation of intermediate imine species. However, Endicott and coworkers [159] have managed to synthesize chromium(III) sepulchrate, not isolating its tris-ethylenediaminate, upon heating of anhydrous chromium sulphate with concentrated aqueous ethylenediamine for several hours followed by the addition of formaldehyde and ammonia with constant heating. The... 

Goedken and Peng s idea to employ the reaction between the amino groups, bound to the metal ion, and formaldehyde for the synthesis of clathrochelates proved to be beneficial. It has served as a basis for later studies of Sargeson and coworkers on the synthesis of sepulchrates and sarcophaginates. 

Similar approaches have been employed by Sargeson and coworkers to investigate the kinetics of metal ion extrusion from presynthesized d-metal (in particular, copper(II)) sarcophaginates in acidic media [4, 5, 174],... 

Analysis of kinetic and structural data permitted Sargeson and coworkers to establish a mechanism of Cu ion extrusion from a sarcophaginate cavity [4, 5]. A spontaneous Cu-N bond rupture via a dissociative mechanism takes place at the first stage. It accounts for the fact that the rate of transition of a clathrochelate complex to a square-planar one is independent of the concentration of ion. Then noncoordinated amino group protonates and a second amino group of the same ethylenediamine moiety coordinates in the apical position... 

When the platinurh catalyst is not present and the solution is oxygen-saturated, the [Co(sep)]2+ complex produced on excitation is reoxidized to [Co(sep)] + cation by oxygen. Such a reaction, thoroughly studied by Sargeson and coworkers, is known to proceed by the steps... 

Sargeson and coworkers have synthesized a number of thioether cryptate sexidentates including 321)1092 (322)" condensing the appropriate trithiol with aziridine. The trigonally positioned... 

Few cobalt complexes exist containing coordinated tetrahedral perchlorate, and those which do show weak coordination. Table 75 gives some structural data. Early reports on the isolation of [Co(OC10j)(NH3)5](C104)2 are erroneous but Sargeson and coworkers have prepared it as pink crystals by nitrosation of [CoNj(NHj)5](a04)2 in concentrated HCIO4. Coordinated perchlorate is rapidly displaced by water in aqueous solution (ri/2 7 s) and cobalt in any oxidation state prefers almost any other donor atom over perchlorate oxygen. 

Sargeson and coworkers studied the hydration of coordinated carboxyalkenes using bis(aIkanediamine)cobalt(in) complexes with either methyl maleate or ethyl fuma-rate cis coordinated to a water molecule [12] (Fig. 1). 

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