1370733-78-0Relevant articles and documents
Mechanochemical and solution synthesis, and crystal structures and IR and solid-state (CPMAS) NMR spectroscopy of some bis(triphenylphosphine)silver(i) mono- and di-hydrogencitrate systems
Bowmaker, Graham A.,Hanna, John V.,Skelton, Brian W.,White, Allan H.
, p. 5409 - 5417 (2012/05/20)
The complex [(Ph3P)2Ag(H2cit)]·EtOH (1; H2cit- = dihydrogencitrate = C6H 7O7-) contains [(Ph3P) 2Ag(H2cit)] molecules in which the silver atom is coordinated to two PPh3 molecules and the two oxygen atoms of one of the 'terminal'/1-carboxylate groups of the dihydrogencitrate group. The molecules form centrosymmetric hydrogen-bonded dimers in the solid. In [{(Ph3P)2Ag}2(Hcit)], (2), unsymmetrical deprotonation of the citrate grouping is found, from the 1- and 3- (i.e. terminal and central) carboxylates: [(Ph3P)2Ag(O 2CCH2C(OH) (CH2COOH)CO2)Ag(PPh 3)2]. The above complexes, as well as [(Ph 3P)3Ag(H2cit)] (3) were prepared via conventional solution methods, involving the reaction of trisilver(i) citrate, citric acid and triphenylphosphine, and by a mechanochemical method involving the reaction of silver(i) oxide, citric acid and triphenylphosphine. IR studies of 1-3 show the presence of coordinated carboxylate and free carboxylic acid groups in the mono- and di-hydrogencitrate ligands, and the formation of 2 from 1 shows that dihydrogencitrate deprotonation can occur upon dissolution of 1 in protic solvents. High-field (9.40 T) 31P CPMAS NMR spectra were recorded and analysed, yielding heteronuclear 1J( 107/109Ag,31P) and homonuclear 2J( 31P,31P) spin-spin coupling constants.