1467018-06-9Relevant academic research and scientific papers
Extremely bulky amido and amidinato complexes of boron and aluminium halides: Synthesis and reduction studies
Wong, Edwin W.Y.,Dange, Deepak,Fohlmeister, Lea,Hadlington, Terrance J.,Jones, Cameron
, p. 1144 - 1154 (2013/10/22)
An extremely bulky secondary amine, HN(Ar?)(SiPr3i) HL? (Ar?≤C6H2{C(H)Ph2}2Pri-2,6,4) has been synthesised and deprotonated with KH in toluene, to afford the potassium amide [KL?(η6-toluene)], which was structurally authenticated. Reaction of this with BBr3 and AlBr3, reproducibly gave the crystallographically characterised amido bromo-borane, [L?B(H)Br], and aluminacycle, [AlBr2{2-C,N-N(H)(SiPr3i){C6H2[CPh2][C(H) Ph2]Pri-2,6,4}}], respectively, via ligand C-H activation processes. The known secondary amines, HN(Dip)(Mes) (HLMes) and HN(Dip)(Trip) (HLTrip) (Dip≤2,6-diisopropylphenyl, Mes≤mesityl, Trip≤2,4,6-triisopropylphenyl) , have been structurally characterised, and deprotonated to give the in situ generated lithium amides, [Li(LMes)] and [Li(LTrip)]. Reaction of these with BBr3 and AlBr3 has given the amido group 13 element halide complexes, [LMesBBr2] and [LAlBr2(THF)] (L≤LMes or LTrip), the crystal structures of all of which have been determined. Synthetic routes to two new bulky amidine pro-ligands, ArN≤C(But)-N(H)Ar, Ar≤C6H2{C(H)Ph2}2Me-2,6,4 (Piso*H) or C6H2Pr2i(CPh3)-2,6,4 (Piso″H), have been developed, and the compounds crystallographically characterised. Deprotonation of Piso″H gave the potassium amidinate, [K(Piso″)], which was reacted with BBr3 to give [(Piso″)BBr2]. Reaction of Piso″H with AlMe3 afforded [(Piso″)AlMe2], which, when treated with I2 yielded [(Piso″)AlI2], the crystal structure of which was determined. Reductions of all of the prepared amido and amidinato group 13 element(iii) halide complexes were attempted using a variety of reducing reagents, with a view to prepare boron(i) or aluminium(i) complexes. While these were not successful, this study does offer synthetic inorganic chemists a variety of new very bulky anionic N-donor ligands, and boron/aluminium halide complexes thereof, for use in their own research.
