ic5017033_si_003.cif (9.69 kB)

Activation of Nitrogen Brønsted Acids: Synthesis and Reactivity of a New Class of Nitrogen Acid Complexes

Download (9.69 kB)
posted on 20.10.2014 by D. Scott Bohle, Zhijie Chua
The nitrogen acids RC­(O)­NHNO2, N-nitroamide, R = CH3 (1), C2H5 (2) and N-nitrocarbamate, R′OC­(O)­NHNO2, R′ = CH3 (3), C2H5 (4) are a class of primary N-nitrocarboxamide compounds that oxidatively add to trans-Ir(I)(Cl)­(N2)­(PPh3)2 to give six-coordinate Ir(III)2-(NO2)-nitrogen acid)­(H)­(Cl)­(PPh3)2 complexes 58. Unexpected fluxional behavior of the complexes in solution is observed by 1H NMR spectroscopy. Reaction intermediates of the oxidative addition reactions were also observed and monitored using 31P and 1H NMR and solution IR spectroscopies. Complex 5 reacts with methyl triflate in CH3CN to generate bis­(acetonitrile) complex (9) from a net loss of the nitrogen acid anion. P­(CH3)2Ph reacts with 5 to give phosphine-substituted and P­(CH3)2Ph addition isomers (10). Reactivity studies of 5 with CO gave metastable CO adduct isomer 11, which loses CO on prolonged standing in solution.