28098-23-9Relevant articles and documents
Activation of the BCO unit in the ketenylidene analogue (μ-H)3Os3(CO)9(μ3-BCO) by electrophiles: Syntheses of vinylidene and alkyne analogues
Workman, David P.,Jan, Deng-Yang,Shore, Sheldon G.
, p. 3518 - 3525 (2008/10/08)
The Lewis acids BX3 (X = Cl, Br), BH3, B-Cl-9-BBN, and PhBCl2 react with (μ-H)3Os3(CO)9(μ3-BCO) (I), a ketenylidene analogue, apparently through electrophilic attack at the oxygen of the unique carbonyl. Reactions of I with BX3 (X = Cl, Br) result in an exchange of B and C atom positions in the BCO unit to form a vinylidene analogue, (μ-H)3Os3(CO)9(μ3-CBX 2). Boron-10-labeling experiments indicate that this transformation occurs through an intramolecular interchange of the boron and carbon atom positions. The ketenylidene analogue (μ-H)3Os3(CO)8(PPh3)(μ 3-BCO) reacts similarly with BCl3 to produce (μ-H)3Os3(CO)8(PPh3)(μ 3-CBCl2). The nucleophiles PMe3, PPh3, and NMe3 add to the tricoordinate boron of (μ-H)3Os3-(CO)9(μ3-CBCl 2). Above -10°C the NMe3 adduct is converted to the salt [NMe3H][(μ-H)2Os3(CO)9(μ 3-CBCl2)] and the PMe3 adduct dissociates. The PPh3 adduct decomposes above 30°C. The reaction of (μ-H)3Os3(CO)9(μ3-BCO) with THF·BH3 produces (μ-H)3Os3(CO)9(μ3-BCH 2), a second type of vinylidene analogue. In this case the boron and carbon atoms do not change positions. Alkyne analogues, (μ-H)3Os3(CO)9[μ3-η 2-C(OBC8H14)B(Cl)] and (μ-H)3Os3(CO)9[μ3-η 2-C{OB(Ph)Cl}B(Cl)] are obtained from reactions of (μ-H)3Os3(CO)9(μ3-BCO) with B-Cl-9-BBN and PhBCl2. These compounds react with BCl3 to produce (μ-H)3Os3(CO)9(μ3-CBCl 2). They also react with HCl to produce (μ-H)3Os3(CO)9(μ3-CH).
