Tris(pyrazolyl)hydroborato]magnesium alkyl derivatives: synthetic and structural studies

Abstract

A series of solvent-free, monomeric, (tris pyrazolyl)hydroborato)magnesium alkyl derivatives, {η 3 -HB-(3-Bu t pz) 3 }MgR and {η 3 -HB(3,5-Me 2 pz) 3 }MgR (3-Bu t pz=3-C 3 N 2 Bu t H 2 ; 3,5-Me 2 pz=3,5-C 3 N 2 Me 2 H; R=CH 3 , CH 2 CH 3 , CH(CH 3 ) 2 , C(CH 3 ) 3 , CH 2 (CH 2 ) 2 CH 3 , CH 2 Si(CH 3 ) 3 , CH=CH 2 , C 6 H 5 ), have been prepared by the reaction of the appropriate dialkylmagnesium compound with either the potassium or thallium derivatives of the respective tris(pyrazolyl)hydroborato ligand. The molecular structures of the complexes have been determined by X-ray diffraction, which shows that in each case the complexes are monomeric with 4-coordinate magnesium centers and η 3 -coordinate tris(pyrazolyl)hydroborato ligands