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Titolo:
Isomerisation and fragmentation of sulfur-containing organometallacycles on dicobalt centres induced by phosphorus donor ligands
Autore:
King, JD; Mays, MJ; Pateman, GE; Raithby, PR; Solan, GA; Conole, G; McPartlin, M;
Indirizzi:
Univ Cambridge, Dept Chem, Cambridge CB2 1EW, England Univ Cambridge Cambridge England CB2 1EW hem, Cambridge CB2 1EW, England Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England Univ Leicester Leicester Leics England LE1 7RH er LE1 7RH, Leics, England Univ N London, Sch Appl Chem, London N7 8DB, England Univ N London London England N7 8DB ch Appl Chem, London N7 8DB, England
Titolo Testata:
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
fascicolo: 2, , anno: 2001,
pagine: 202 - 210
SICI:
1472-7773(2001):2<202:IAFOSO>2.0.ZU;2-0
Fonte:
ISI
Lingua:
ENG
Soggetto:
DINUCLEAR METAL CENTERS; MOLECULAR-STRUCTURES; ORGANIC-CHEMISTRY; PHOSPHIDO BRIDGE; BOND-CLEAVAGE; C-H; COMPLEXES; THIOPHENE; CRYSTAL; ALKYNES;
Keywords:
cobalt; isomerism; mechanisms in solution; organometallic; P; N; S; Se; O; Te; Si-containing ligands;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
41
Recensione:
Indirizzi per estratti:
Indirizzo: Mays, MJ Univ Cambridge, Dept Chem, Lensfield Rd, Cambridge CB2 1EW, England Univ Cambridge Lensfield Rd Cambridge England CB2 1EW W, England
Citazione:
J.D. King et al., "Isomerisation and fragmentation of sulfur-containing organometallacycles on dicobalt centres induced by phosphorus donor ligands", J CHEM S DA, (2), 2001, pp. 202-210

Abstract

Treatment of the dibridged dicobalt complex [Co-2(mu -PPh2){mu-eta (1)(S) : eta (1)(C) : eta (2)(C)-SPhC(O)CR'CR}(CO)(4)] (R' = R = H 1a) with L, at ambient temperature, affords an inseparable mixture of two mono-substitutedisomeric complexes of general formula [Co-2(mu -PPh2){mu-eta (1)(S) : eta (1)(C) : eta (2)(C)-SPhC(O)CHCH}(CO)(3)(L)] [L = P(OMe)(3) 2a/3a, PPhMe2 2b/3b], differing only in the metal centre at which L is coordinated. When the reaction is performed with [Co-2(mu -PPh2){mu-eta (1)(S) : eta (1)(C) : eta (2)(C)-SPhC(O)CR'CR}(CO)(4)] [R' = Me, R = H 1b], in which R' and R are inequivalent, a similar mixture of inseparable isomers is isolated, [Co-2(mu -PPh2){mu-eta (1)(S) : eta (1)(C) : eta (2)(C)-SPhC(O)CMeCH}(CO)(3)(L)] [L = P(OMe)(3) 4a/5a, PPhMe2 4b/5b] and, in addition, a third separable isomer, [Co-2(mu -PPh2){mu-eta (1)(S) : eta (1)(C) : eta (2)(C)-SPhC(O)CHCMe}(CO)(3)(L)] [L = P(OMe)(3), 6a, PPhMe2 6b], in which R' and R have interchanged. Addition of a further equivalent of L at elevated temperature to mixtures of 2/3 results in both carbonyl substitution and a rearrangement of the bridging ligand assembly to give [Co-2(mu -SPh){mu-eta (1)(P) : eta (1)(C) : eta (2)(C)-PPh2CRCR'C(O)}(CO)(2)(L)(2)] [R' = R = H; L = P(OMe)(3) 7a, PPhMe2 7b] in high yield. A similar transformation is achieved on interactionof 4/5 and 6 with L leading to [Co-2(mu -SPh){mu-eta (1)(P) : eta (1)(C) :eta (2)(C)-PPh2CRCR'C(O)}(CO)(2)(L)(2)] [R' = Me, R = H; L = P(OMe)(3) 8a,PPhMe2 8b] and, in addition, [Co-2(mu -SPh){mu-eta (1)(P) : eta (1)(C) : eta (2)(C)-PPh2CR'CRC(O)}(CO)(2)(L)(2)] [R' = Me, R = H; L = P(OMe)(3) 9a, PPhMe2, 9b], in which the positions of R' and R are reversed. Reaction of 2a/3a with triphenylphosphine, gives the mixed phosphite-phosphine rearrangedspecies [Co-2(mu -SPh){mu-eta (1)(P) : eta (1)(C) : eta (2)(C)-PPh2CHCHC(O)}(CO)(2){P(OMe)(3)}(PPh3)] 10 as the sole product. The facility of the bridging ligands in 1 to undergo a range of bond-breaking (C-S and C-C) and bond-forming (C-S, C-P and C-C) reactions induced by phosphorus donor ligand addition is discussed and pathways postulated. The single crystal X-ray structures of 2b, 7a and 10 are described.

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Documento generato il 29/03/20 alle ore 08:19:01