Arene ruthenium β-diketonato triazolato derivatives: Synthesis and spectral studies (β-diketones: 1-phenyl-3-methyl-4-benzoyl pyrazol-5-one, acetylacetone derivatives)

Mononuclear neutral arene ruthenium(II) β-diketonato complexes of the general formula (η6-arene)Ru(LL)Cl [LL = 1-phenyl-3-methyl-4-benzoyl pyrazol-5-one (L1), arene = C6H6 (1), p-iPrC6H4Me (2), C6Me6 (3); arene = p-iPrC6H4Me, LL = 1-benzoylacetone (L3) (8); arene = p-iPrC6H4Me, LL = dibenzoylmethane (L4) (9)] have been synthesized and their subsequent substitution reactions with NaN3 in alcohol at room temperature yielded the corresponding neutral terminal azido complexes (η6-arene)Ru(LL)N3 [LL = 1-phenyl-3-methyl-4-benzoyl pyrazol-5-one (L1), arene = C6H6 (4), p-iPrC6H4Me (6), C6Me6 (7); arene = p-iPrC6H4Me, LL = dibenzoylmethane (L4) (10)] as well as a cationic complex [(η6-p-iPrC6H4Me)Ru(L4) (PPh3)]BF4 (12) with PPh3. The [3 + 2] cycloaddition reaction of selective azido complexes with the activated alkynes dimethyl and diethyl acetylenedicarboxylates produced the arene triazolato complexes [(η6-arene)Ru(LL){N3C2(CO2R)2}] [arene = p-iPrC6H4Me, LL = L1, R = Me (13); arene = C6Me6, LL = L1, R = Me (14); arene = C6Me6, LL = acetyl acetone (L2), R = Me (15); arene = C6Me6, LL = L3, R = Me (16); arene = p-iPrC6H4Me, LL = L1, R = Et (17); arene = C6Me6, LL = L1, R = Et (18); arene = C6Me6, LL = L2, R = Et (19); arene = C6Me6, LL = L3, R = Et (20)]. With fumaronitrile the reaction yielded the triazoles [(η6-arene)Ru(LL)(N3C2HCN)] [arene = p-iPrC6H4Me, LL = L1 (21), arene = C6Me6, LL = L1 (22), arene = C6Me6, LL = L2 (23), arene = C6Me6, LL = L3 (24)]. In the above triazolato complexes only N(2) isomer was obtained. The complexes were characterized on the basis of spectroscopic data. Crystal structure of representatives complexes were determined by single crystal X-ray diffraction.

Arene ruthenium azide complexes bearing functionalized β-diketonato ligands have been synthesized. These complexes undergo 3 + 2 cycloaddition reactions with activated alkynes to yield triazolato compounds. These complexes were characterized by spectral studies and representative complexes by single crystal X-ray studies.Figure optionsDownload as PowerPoint slide