H+/AuPPh3+ Exchange for the Hydride Complexes CpMoH(CO)2(L) (L = PMe3, PPh3, CO). Formation and Structure of [Cp(CO)2(PMe
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- 作者：Rossana Galassi ; Rinaldo Poli ; E. Alessandra Quadrelli ; and James C. Fettinger
- 刊名：Inorganic Chemistry
- 出版年：1997
- 出版时间：July 2, 1997
- 年：1997
- 卷：36
- 期：14
- 页码：3001 - 3007
- 全文大小：258K
- 年卷期：v.36,no.14(July 2, 1997)
- ISSN：1520-510X
文摘
The reaction of CpMoH(CO)2L withAuPPh3+BF4- inTHF at -40 
C proceeds directly to the MoAu2clustercompounds[CpMo(CO)2L(AuPPh3)2]+BF4-(L = PMe3 (1), PPh3(2)) with release of protons. A 1:1reactionleaves 50% of the starting hydride unreacted. At lowertemperature, however, the formation of a[CpMo(CO)2(PMe3)(
-H)(AuPPh3)]+intermediate is observed. This compound evolves to the cation of1 and CpMoH(CO)2(PMe3) upon warming and is deprotonated by 2,6-lutidine toaffordCpMo(CO)2(PMe3)(AuPPh3).The X-raystructure of 1 can be described as a four-legged piano stoolwith the PMe3 and the"
2-(AuPPh3)2" ligandsoccupyingrelative trans positions.[Cp(CO)2(PMe3)Mo(AuPPh3)2]+[BF4]-(Mr = 1298.41): monoclinic, space groupP21/n, a = 18.1457(13) Å, b =9.7811(7) Å, c = 26.096(2) Å, 
=105.086(5), V = 4472.0(5) Å3,Z = 4. Thereaction of CpMoH(CO)2(PMe3) with 3equiv of AuPPh3+ affords a MoAu3cluster,[CpMo(CO)2(PMe3)(AuPPh3)3]2+ (3), ingood yields under kinetically controlled conditions. Underthermodynamically controlledconditions, 3 dissociates extensively into 1 andfree AuPPh3+. It is proposed that thehydride ligand helps buildhigher nuclearity Mo-Au clusters. The difference in reactionpathways for the interaction of AuPPh3+withCpMoH(CO)2L when L = PR3 or CO and forthe interaction of CpMoH(CO)2(PMe3)with E+ when E = H, Ph3Cor AuPPh3 is discussed. The lower acidity and greateraurophilicity of the[CpMo(CO)2L(-H)(AuPPh3)]+intermediate when L = PMe3 favor attack byAuPPh3+ before deprotonation.
C proceeds directly to the MoAu2clustercompounds[CpMo(CO)2L(AuPPh3)2]+BF4-(L = PMe3 (1), PPh3(2)) with release of protons. A 1:1reactionleaves 50% of the starting hydride unreacted. At lowertemperature, however, the formation of a[CpMo(CO)2(PMe3)(-H)(AuPPh3)]+intermediate is observed. This compound evolves to the cation of1 and CpMoH(CO)2(PMe3) upon warming and is deprotonated by 2,6-lutidine toaffordCpMo(CO)2(PMe3)(AuPPh3).The X-raystructure of 1 can be described as a four-legged piano stoolwith the PMe3 and the"2-(AuPPh3)2" ligandsoccupyingrelative trans positions.[Cp(CO)2(PMe3)Mo(AuPPh3)2]+[BF4]-(Mr = 1298.41): monoclinic, space groupP21/n, a = 18.1457(13) Å, b =9.7811(7) Å, c = 26.096(2) Å, =105.086(5), V = 4472.0(5) Å3,Z = 4. Thereaction of CpMoH(CO)2(PMe3) with 3equiv of AuPPh3+ affords a MoAu3cluster,[CpMo(CO)2(PMe3)(AuPPh3)3]2+ (3), ingood yields under kinetically controlled conditions. Underthermodynamically controlledconditions, 3 dissociates extensively into 1 andfree AuPPh3+. It is proposed that thehydride ligand helps buildhigher nuclearity Mo-Au clusters. The difference in reactionpathways for the interaction of AuPPh3+withCpMoH(CO)2L when L = PR3 or CO and forthe interaction of CpMoH(CO)2(PMe3)with E+ when E = H, Ph3Cor AuPPh3 is discussed. The lower acidity and greateraurophilicity of the[CpMo(CO)2L(-H)(AuPPh3)]+intermediate when L = PMe3 favor attack byAuPPh3+ before deprotonation.