1428586-01-9Relevant academic research and scientific papers
β-diketiminato nickel imides in catalytic nitrene transfer to isocyanides
Wiese, Stefan,Aguila, Mae Joanne B.,Kogut, Elzbieta,Warren, Timothy H.
supporting information, p. 2300 - 2308 (2013/06/27)
The β-diketiminato nickel(I) species [Me3NN]Ni(2-picoline) (1) serves as an efficient catalyst for carbodiimide (RN=C=NR′) formation in the reactions of a range of organoazides N3R with isocyanides R′NC. [Me3NN]Ni(CNR)2 (R = tBu, Ar (Ar = 2,6-Me2C6H3)) species provide carbodiimides RN=C=NAr′ upon reaction with Ar′N3 (Ar′ = 3,5-Me2C6H3). Nitrene transfer takes place via the intermediacy of nickel imides. Reaction of [MexNN]Ni(2-picoline) (x = 2 or 3) with Ar′N3 gives the new dinickel imides {[Me xNN]Ni}2(μ-NAr′) (4 (x = 3) and 5 (x = 2)) as deep purple, diamagnetic substances. The X-ray structure of {[Me 2NN]Ni}2(μ-NAr′) (5) features short Ni-N imide distances of 1.747(2) and 1.755(2) A along with a short Ni-Ni distance of 2.7210(3) A. These dinickel imides 4 and 5 react stoichiometrically with tBuNC to provide the corresponding carbodiimides tBuN=C=NAr′ in good yield. Azide transfer takes place upon reaction of 1 with TMS-N3 to give the square planar nickel(II) azide [Me3NN]Ni(N3)(2-picoline) (7). Stoichiometric reaction of dinickel dicarbonyl {[Me3NN]Ni} 2(μ-CO)2 with organoazides such as Ar′N 3 is sluggish, indicating that 1 is not an efficient catalyst for nitrene transfer from organoazides to CO to form isocyanates RN=C=O.
