Activation of Strong Boron-Fluorine and Silicon-Fluorine sigma-Bonds: Theoretical Understanding and Prediction

作者：Kameo Hajime^*; Sakaki Shigeyoshi

来源：Chemistry - A European Journal, 2015, 21(39): 13588-13597.

DOI：10.1002/chem.201502197

• BF bonds
• bond activation
• density functional calculations
• platinum
• SiF bonds

The oxidative addition of BF3 to a platinum(0) bis(phosphine) complex [Pt(PMe3)(2)] (1) was investigated by density functional calculations. Both the cis and trans pathways for the oxidative addition of BF3 to 1 are endergonic (G degrees=26.8 and 35.7kcalmol(-1), respectively) and require large Gibbs activation energies (G degrees=56.3 and 38.9kcalmol(-1), respectively). A second borane plays crucial roles in accelerating the activation; the trans oxidative addition of BF3 to 1 in the presence of a second BF3 molecule occurs with G degrees and G degrees values of 10.1 and -4.7kcalmol(-1), respectively. G degrees becomes very small and G degrees becomes negative. A charge transfer (CT), FBF3, occurs from the dissociating fluoride to the second non-coordinated BF3. This CT interaction stabilizes both the transition state and the product. The BF sigma-bond cleavage of BF2ArF (Ar-F=3,5-bis(trifluoromethyl)phenyl) and the BCl sigma-bond cleavage of BCl3 by 1 are accelerated by the participation of the second borane. The calculations predict that trans oxidative addition of SiF4 to 1 easily occurs in the presence of a second SiF4 molecule via the formation of a hypervalent Si species.

• 出版日期2015-9-21