137515-90-3

Upstream product

• 3433-80-5 1-Bromo-2-bromomethyl-benzene 
• 137515-87-8 {Ni₂(CH₂C₆H₄)Br₂(P(CH₃)3)3} 
• 119072-55-8 tert-butylisonitrile 

Relevant academic research and scientific papers

Isocyanide insertion chemistry. Synthesis and structural characterization of bridging imidoyl complexes of nickel and amide formation by intramolecular coupling of acyl and imidoyl functionalities

The binuclear pseudoallyl complex trans-(Me3P)BrNi(μ2-η3:η 1-CH2-o-C6H4)NiBr(PMe 3)2 (1) inserts selectively 1 equiv of CNXy (Xy = 2,6-dimethylphenyl) into the Ni-benzylic bond with formation of the cyclic complex trans-(Me3P)2BrNi(C(NXy)CH2-o-C 6H4)NiBr(PMe3) (2) that contains a bridging η2-imidoyl ligand. The analogous reaction of 1 with CNBut gives a related μ2,η2-imidoyl species 3a which, in contrast to 2, exists in solution in thermodynamic equilibrium with its isomer trans-(Me3P)BrNi(η2-C(NBut)CH 2-o-C6H4)NiBr(PMe3)2 (3b), in which the imidoyl ligand is terminally bonded in a η2 fashion to one of the nickel centers. Variable temperature NMR studies show 3b is the kinetic product of the insertion reaction and that the strongly solvent dependent equilibrium 3a ? 3b is attained only at sufficiently high temperatures (ca. -20°C). At even higher temperatures (ca. 40°C), the 3a-3b mixtures convert into a third isomeric compound, trans-(Me3P)2Ni(C(NBut)C6H 4-o-CH2)NiBr(PMe3) (4), in a process which formally corresponds to the deinsertion of CNBut from the Ni-benzyl bond followed by reinsertion into the Ni-aryl moiety. In a rather complex reaction 2 interacts with CO to afford the mononuclear complex trans-Ni(C=CHC6H4C(O)NXy)Br(PMe3)2 (5) whose formation probably involves the intramolecular coupling of acyl and imidoyl functionalities. Hydrolytic cleavage of the Ni-C bond in 5 provides the corresponding N-aryl-1-isoquinolone 6. Compounds 2 and 3a, have been characterized by X-ray studies. 2 crystallizes in the monoclinic space group P21/n with a = 12.437(3) A?, b = 16.025(2) A?, c = 16.015(2) A?, β = 101.47(1)°, and Z = 4. Crystals of 3a are also monoclinic, space group P21/n, with a = 26.05(1) A?, b = 10.226(1) A?, c = 12.013(2) A?, β = 93.54(12) °, and Z = 4. The μ2,η2-imidoyl functionalities of both complexes exhibit similar structural characteristics.

Binuclear complexes of nickel bridged by hydrocarbon ligands. Isocyanide insertion chemistry and amide formation by intramolecular coupling of acyl and imidoyl functionalities

Ni(cod)(PMe3)2 and the o-, m-, and p-bromobenzyl bromides react, under appropriate conditions, to afford the binuclear complexes Ni2(η2-η3,η1-CH 2C6H4)Br2(PMe3) 3 (1a-c) or Ni2(μ2-η1,η1-CH 2C6H4)Br2-(PMe3) 4 (2b,c). The reaction of the ortho η3-benzylic derivative 1a with isocyanides, CNR, has been investigated, and three different isomeric species have been identified for R = But. The CNC6H3-2,6-Me2 insertion product, 4, reacts with CO to form a Ni(II)-vinyl complex 7 derived from the N-aryl-1-isoquinolone 8, which can be freed by hydrolytic cleavage of the Ni-vinyl bond.