Partial and complete hydrolysis of metal complexes based on monoiminoacenaphthene-1-ones

During the partial hydrolysis of metal complexes with the mono-imino-acenaphthen-1-olate (R-mian) dianion, the nitrogen atom is protonated at the first stage, while the metal–ligand bond is preserved. Further hydrolysis leads to products whose structure depends on the reaction conditions. Hydrolysis by an excess of water leads to the formation of the products with a reduced CN fragment, (amino ketones, R-mianH₂). The complexes based on the dianion of (E)-2-(2,6-diisopropylphenylimino)acenaphthylen-1(2H)-one (dpp-mian) are hydrolyzed by a HBF₄ aqueous solution to give an ammonium salt containing a reduced CN fragment with the proton bound to the ammonium nitrogen atom [(dpp-mainH₃)¹⁺BF₄]. When these compounds interact with an aqueous solution of HCl, the carbonyl group CO is involved, while the acid proton coordinates to the nitrogen atom [(dpp-mainH₃)¹⁺Cl]. MP2 calculations explain the formation of different products. Hydrolysis of the metal complexes, bearing a R-mian radical-anion, by water produces a stoichiometric mixture of R-mianH₂ and R-mian as a result of the R-mianH disproportionation. The reaction of R-mian with lithium aluminum hydride leads to the reduction of both the CN and CO fragments.