Toward Alkane Functionalization Effected with Cp*W(NO)(alkyl)(η3-allyl) Complexes

Abstract

Cp*W(NO)(n-alkyl)(η3-allyl) complexes result from the selective activations of the terminal C−H bonds of alkanes. Consequently, the reactions of prototypical members of this family of complexes with a range of electrophiles and nucleophiles have been explored with a view to developing methods for functionalizing the newly formed alkyl ligands. The two principal complexes investigated in this regard have been Cp*W(NO)(CH2SiMe3)(η3-CH2CHCHMe) (1) and Cp*W(NO)(CH2C6H5)(η3-CH2CHCHMe) (2). It has been found that treatment of 1 and 2 with the oxidant I2 at −60 °C produces Cp*W(NO)I2 and terminally functionalized ICH2SiMe3 and ICH2C6H5, respectively. Oxidation of 1 by H2O2 also results in the loss of the allyl ligand and production of the known oxo peroxo complex Cp*W(O)(η2-O2)(CH2SiMe3). Treatment of 1 and 2 with electrophiles affords the products resulting from addition of the electrophile to the electron-rich terminus of the σ−π distorted allyl ligands in the reactants. Thus, reagents of the type E-X (E = tri...