Amidinate Supported Magnesium Neosilyl Complexes as Multitasking and Competent Catalysts for Hydrosilylation and Hydroboration of Alkenes

A series of amidinato‐supported magnesium neosilyl complexes with the general formula [Mg(CH2SiMe3)‐{RN=C(CH2SiMe3)NR}]2 (R = tBu, 1a; R = Cy, 1b; R = iPr, 1c) were prepared in excellent yields by the insertion of a carbodiimide motif in the magnesium–carbon bond of the magnesium neosilyl complex [Mg(CH2SiMe3)2]. A homoleptic magnesium complex [Mg{tBuN=C(CH2SiMe3)NtBu}2] (2a) was also prepared using [Mg(CH2SiMe3)2] and di‐tert‐butylcarbodiimide in a 1:2 molar ratio in toluene. The molecular structures of all the magnesium complexes 1a‐1c and 2a in their solid state were confirmed by single crystal X‐ray diffraction analysis. Further, complexes 1a‐1c and 2a were employed as single‐site catalysts for hydrosilylation and hydroboration of alkenes. The magnesium complex 1a exhibited excellent efficiency as a multitasking catalyst under mild conditions for hydrosilylation and hydroboration of alkenes to afford the corresponding organosilane and boronate esters in high yields. Both of these atom‐economic reactions demonstrated good functional group tolerance.