Heterolytic H2 Activation by Dihydrogen Complexes. Effects of the Ligand X in [M(X)H2{Ph2P(CH2)3PPh2}2]n<
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- 作者：Eliana Rocchini ; Antonio Mezzetti ; Heinz Rü ; egger ; Urs Burckhardt ; Volker Gramlich ; Alessandro Del Zotto ; Paolo Martinuzzi ; and Pierluigi Rigo
- 刊名：Inorganic Chemistry
- 出版年：1997
- 出版时间：February 12, 1997
- 年：1997
- 卷：36
- 期：4
- 页码：711 - 720
- 全文大小：288K
- 年卷期：v.36,no.4(February 12, 1997)
- ISSN：1520-510X
文摘
Complexes of the general formula[MXH2(dppp)2]n+(M = Ru, Os; X = H, Cl, CO; dppp = 1,3-bis(diphenylphosphino)propane) have been prepared and characterized,and the effect of the donor/acceptor propertiesof X on their structure and acidity has been studied. Thefive-coordinate complexes[MCl(dppp)2]+ (M = Ru(1a), Os (1b)) react with H2 gas inCH2Cl2 to give the complexes[MCl(
2-H2)(dppp)2]+(M = Ru (2a), Os (2b))containing elongated dihydrogen ligands. The molecular structureof 2b has been determined by X-raycrystallography (monoclinic, space groupP21/n with a =13.314(7) Å, b = 18.63(2) Å, c =23.20(2) Å, 
=94.58(6)
, and Z = 4). Chlorohydride[OsH(Cl)(dppp)2] (3b) reacts withH2 gas in the presence ofNa[BPh4]forming [OsH3(dppp)2]+(4b). Protonation of[OsH2(dppp)2] (5b) withHBF4·Et2O also gives 4b.A combinationof X-ray crystallography (monoclinic, space groupP21/n with a =13.392(3) Å, b = 25.306(7) Å, c =21.247(7)Å, = 91.15(2), and Z = 4) and1H and 31P NMR studies indicate that4b is a classical trihydride.Hydridocarbonyls[MH(CO)(dppp)2]+ (M = Ru(6a), Os (6b)) are protonated byF3CSO3H inCD2Cl2 to yield[M(CO)(2-H2)(dppp)2]2+(M = Ru (7a), Os (7b)), which werecharacterized in solution. 7a is stable onlyatlow temperature. Compound 7b is a highly acidicdihydrogen complex with an estimated pKa of-6.
2-H2)(dppp)2]+(M = Ru (2a), Os (2b))containing elongated dihydrogen ligands. The molecular structureof 2b has been determined by X-raycrystallography (monoclinic, space groupP21/n with a =13.314(7) Å, b = 18.63(2) Å, c =23.20(2) Å, =94.58(6), and Z = 4). Chlorohydride[OsH(Cl)(dppp)2] (3b) reacts withH2 gas in the presence ofNa[BPh4]forming [OsH3(dppp)2]+(4b). Protonation of[OsH2(dppp)2] (5b) withHBF4·Et2O also gives 4b.A combinationof X-ray crystallography (monoclinic, space groupP21/n with a =13.392(3) Å, b = 25.306(7) Å, c =21.247(7)Å, = 91.15(2), and Z = 4) and1H and 31P NMR studies indicate that4b is a classical trihydride.Hydridocarbonyls[MH(CO)(dppp)2]+ (M = Ru(6a), Os (6b)) are protonated byF3CSO3H inCD2Cl2 to yield[M(CO)(2-H2)(dppp)2]2+(M = Ru (7a), Os (7b)), which werecharacterized in solution. 7a is stable onlyatlow temperature. Compound 7b is a highly acidicdihydrogen complex with an estimated pKa of-6.