Reactivity of Homoleptic Dianionic β‑Diketiminato-Supported Yttrium Complexes toward CS2: Construction of Neutral or Anionic Dihydropyridinethione

The mixed mono- and dianionic β-diketiminato yttrium complex [η2-N,N-{N­(2,6-iPr2­C6H3)­C­(Me)}2­CH]­Y­[η2-N,N-N­(2,6-iPr2­C6H3)­C­(Me)­CHC­(CH2)­N­(C6H3-iPr2-2,6)] (1) was synthesized in almost quantitive yield by the metathesis reaction of β-diketiminato potassium with YCl3 in a 3:1 molar ratio in THF at room temperature. Complex 1 reacted with 1 equiv of KCH2Ph under the same conditions to afford a linear dianionic β-diketiminato-supported Y­(III)/​K­(I) heterobimetallic polymer {Y­[μ-η2:​η1-N,N-N­(2,6-iPr2­C6H3)­C­(Me)­CHC­(CH2)­N­(C6H3-iPr2-2,6)]2-K­(THF)3}∞ (2). Moreover, 2 can be transformed into the corresponding salt-type complexes [K­([2.2.2]­cryptand)]+­{[η2-N,N-N­(2,6-iPr2­C6H3)­C­(Me)­CHC­(CH2)­N­(C6H3-iPr2-2,6)]2­Y}− (3) and [nBn4N]+­{[η2-N,N-N­(2,6-iPr2­C6H3)­C­(Me)­CHC­(CH2)­N­(C6H3-iPr2-2,6)]2­Y}− (4) in high yields by the reactions of 2 with [2,2,2]-cryptand or nBu4­NCl in THF, respectively. The reaction of 3 and 4 with 2 equiv of CS2 in THF at amibent temperature gave the anionic or neutral aryl-substituted dihydro­pyridine­thione [K­([2.2.2]­cryptand)]+­[2-S,4-N­(Ar),6-Me­C5H2N­(Ar)]−·[2-S,4-N­(H)­Ar,6-Me­C5H2N­(Ar)] (5) and 2-S,4-N­(H)­Ar,6-Me­C5H2N­(Ar) (6) in moderate yields, accompanied by unidentified materials containing Y3+ ions, respectively. The formation of 5 and 6 revealed an intermolecular nucleophilic addition/​cyclization and some chemical bond transformations such as C–C and C–N formation, CS cleavage, and 1,3-hydrogen shift occurred in the above reactions. The molecular structures of all of these new complexes 1–6 have been determined through X-ray single-crystal diffraction analysis.