[2-(Alkylideneamino)benzoato]nickel(II) Complexes:  Active Catalysts for Ethylene Polymerization

Abstract

The complexes [RR′CdNC 6 H 4 C(O)O-κ 2 N,O]Ni(η 3 -CH 2 CMeCH 2 ) (R, R′ ) -(CH 2 ) 5 -, 6; R ) Et, R′ ) Et, 7; R ) tBu, R′ ) H, 8) are prepared by reaction of the corresponding potassium salts with 11), which give poly(ethylene) when ethylene gas is added. This result is interesting in that the corresponding 2-(diphenylphosphino)benzoato and 2-(diphenylamino)benzoato complexes give mainly butene. Reactions of the potassium salts with Ni(η 3 -CH 2 C 6 H 5 )Cl(PMe 3 ) afford benzyl complexes,Additions of 2 equiv of B(C 6 F 5 ) 3 to 12 and 13 afford the zwitterionic). Complex 14 is rather unstable, and a bis ligand complex, [(CH 2 ) 5 CdNC 6 H 4 C{OB(C 6 F 5 ) 3 }O-κ 2 N,O] 2 Ni (16), is formed during recrystallization. Complexes 14 and 15 are highly active to ethylene polymerization, and activities reach 3000-4000 kg/((mol of Ni) h) at 75 psig pressure. Solid structures of 6, 9, 11, 15, and 16 were determined by X-ray crystallography.

Synthesis of Uniquely Branched Polyethylene by Anilinonaphthoquinone Ligated Nickel Complex Activated with Tris(pentafluorophenyl)borane

“…13 C NMR spectra of the polyethylenes were measured at 120 8C on a JEOL GX 500 spectrometer operated at 125.65 MHz in the pulse Fourier Transform mode. The pulse angle was 458 and about 4 000-8 000 scans were accumulated with a pulse repetition of 5.0 s. Sample solutions were prepared in 1,1,2,2-tetrachloroethane-d 2 up to 10 wt.-%.…”

“…1 H NMR (C 6 D 6 ): d ¼ 8.13 (dd, J ¼ 1.2, 7.5 Hz, 1H), 7.95 (dd, J ¼ 1.2, 7.5 Hz, 1H), 7.07 (dt, J ¼ 1.2, 7.5 Hz, 1H), 7.00 (dt, J ¼ 1.2, 7.5 Hz, 1H), 6.89 (d, J ¼ 7.5 Hz, 1H), 6.79 (d, J ¼ 7.5 Hz, 2H), 6.07 (d, J ¼ 8.1 Hz, 1H), 6.57 (br, 1H), 5.66 (s, 1H), 2.85 (sept, J ¼ 6.9 Hz, 1H), 0.95 (d, J ¼ 6.9 Hz, 6H), 0.91 (d, J ¼ 6.9 Hz, 6H). 13 C NMR (C 6 D 6 ): d ¼ 182.4, 182. 2, 148.4, 146.6, 134.7, 134.1, 131.9, 131.5, 131.0, 129.2, 126.5, 126.2, 124.4, 103.7, 28.8, 24 …”

“…13 C NMR (1,1,2,2-tetrachloroethane-d 2 , 120 8C, 125 MHz) spectra of the polyethylenes obtained using 1 (a, entry 2) and 1-B(C 6 F 5 ) 3 (b, entry 4).…”

Olefin Polymerization with Non-metallocene Catalysts (Late Transition Metals)

“…The produced complex catalyze ethylene polymerization without addition of co-catalyst [131]. Zwitterionic complex formed by the reaction of B(C 6 F 5 ) 3 with (2-(alkylideneamino or diphenylamino)benzoate)nickel complex (7f) promotes dimerization or polymerization depending on the N-substituents [132].…”

A zwitterionic nickel–olefin initiator for the preparation of high molecular weight polyethylene

“…Examination of ligand/reactivity relationships for cationic Ni(diimine) initiators [2,8] led to the design and synthesis of {(H 3 C)C[@NAr]C[O-B(C 6 F 5 ) 3 ][@NAr]-j 2 N,N 0 }-Ni(g 3 -CH 2 C 6 H 5 ), with which high molecular weight polyethylene (PE) can be produced for bulky aromatic (Ar) substituents [9]. Several other ligand types have been reported that are amenable to the concept of Lewis acid attachment on a ligand site to redistribute electron density, including 3-(1-arylimino-ethyl)-acetylacetonato [10], 2-diphenylphosphinylbenzamido [11], N-(2-benzoylphenyl)-benzamido [12], a-iminoenamido [13], 2-(alkyldeneamino)-benzoato [14] and iminoamido pyridine [15], However, none of these systems have been able to produce high molecular weight PE in the absence of bulky Ar substituents.…”