216389-51-4

Upstream product

• 144422-45-7 Mg(C₆H₅C(NSi(CH₃)3)2)2(C₄H₈O)2 
• 854377-00-7 bis[bis(trimethylsilyl)benzamidinato]dinickel(I) 

Relevant academic research and scientific papers

Synthesis and molecular structures of neutral nickel complexes. Catalytic activity of (Benzamidinato)(acetylacetonato)nickel for the addition polymerization of norbornene, the oligomerization of ethylene, and the dimerization of propylene

The new neutral nickel complexes PhC(NSiMe3)2Ni(acac) (3), PhC(NSiMe3)2Ni(acac)-(TMEDA) (4), [PhC(NSiMe 3)2]2Ni2 (5), [PhC(NSiMe 3)2]2Ni·Li2Br 2(TMEDA)2 (6), (TMEDA)2Ni (7), p-MePhC(NSiMe3)2Ni(acac) (8), p-MePhC(NSiMe 3)2Ni(acac)(TMEDA) (9), [p-MePhC-(NSiMe3) 2]2Ni (10), NiMe2Py2 (11) and [p-MePhC(NSiMe3)]2Ni(Py) (14) have been synthesized and characterized. The solid-state molecular structures of all complexes have been confirmed by low-temperature X-ray diffraction analysis. The methyl complex p-MePhC(NSiMe3)2Ni(Me)(Py) (13) is not stable and rapidly decomposes, forming the complex [p-MePhC(NSiMe3)]2-Ni(Py) (14). Complex 3 activated with MAO has been shown to be an efficient catalytic system for the norbornene vinyl-type polymerization. The activity of the catalyst and the molecular weights of the resulting polynorbornenes were found to be dependent on the reaction time, the MAO/precatalyst ratio, and the reaction temperature. In addition, this catalytic system has been found to dimerize propylene to a mixture of hexenes with a high turnover frequency of η = 9040 h-1 and oligomerize ethylene to either a mixture of C4-C6 or/and C4-C14 products, depending on the temperature and the solvent, extremely rapidly (η = 83 500 h-1).

Complexes of the bis(trimethylsilyl)-benzamidinato ligand 'siam': Synthesis and X-ray structures of (siam)2M, (siam) (siamH) MX (M = Ni, Pd), (siam)2MnI and (siam) ReO3, and their reactivity towards CO2

Complexes with the bis(trimethylsilyl)-benzamidinato ligand 'siam' of the type (siam)2M (M = Ni (2), Pd (3)), (siam) (siamH) NiBr (4a), (siam) (siamH)PdCl (4b) and (siam)2MnI (5) were prepared by reaction of (siam)2Mg(thf)2 (1) with the corresponding metal halides and addition of water or iodine, respectively. The reaction of (siam)2Zn with Re2O7 yielded (siam)ReO3 (6). X-ray analysis of 1-6 revealed that siam acts as a bidentate ligand forming four-membered chelate rings in all complexes. In 2 four nitrogen atoms show a distorted tetrahedron; in contrast, 3, 4a and 4b are square planar complexes. In both 4a and 4b siamH is coordinated as a monodentate ligand. The Mn(III) complex 5 exhibits a trigonal bipyramidal coordination of the four amidinato nitrogens and the iodo ligand, which occupies an equatorial position. The Re(VII) complex 6 shows an irregular trigonal bipyramidal coordination. In all compounds the bond lengths and angles in the amidinato ligand are comparable and exhibit typical values. The reaction of 2 with excess CO2 gave a green dimeric complex 7 in which one Ni(II) centre is octahedral and the other is square pyramidal coordinated. X-ray analysis revealed that 5 mol CO2 per 2 mol nickel are inserted in N-Si bonds forming new types of tridentate bridging ligands which contain N-COOSiMe3 groups.