A combined experimental and computational study demonstrates the influence of fluorine substituents on the electronic properties of β-diketiminate ligands.

The synthesis of fluorinated -diketimine LH 1 (L = HC[C(CF 3 )NC 6 F 5 ] 2 ) and its reactions with main-group-metal and transition-metal complexes, yielding LAlMe 2 4, LZnEt 5, LCu(C 6 D 6 ) 6 and LCuCO 7, is reported. 1-7 were characterized [a]

Heteroleptic zinc(i) complexes Cp*Zn–ZnL1/2 were synthesized and reactions of Cp*Zn–ZnL22 with t-BuNCO and organoazides RN3 proceeded with insertion into the Zn–Zn bond and formation of novel zinc carbamate, bis-hexazene, triazenide, and azide complexes 4–7.

Alkane elimination reactions of equimolar amounts of 17Fnac2H (17Fnac2H = FC[C(CF3)NC6F5]2H) with ZnEt2 and AlMe3 as well as 16Fnac2H (16Fnac2H = HC[C(CF3)NC6F5]2H) with GaMe3 yielded the corresponding heteroleptic complexes of 17Fnac2ZnEt (1), 17Fnac2AlMe2 (2), and 16Fnac2GaMe2 (3), whereas reactions of two equivalents of 16Fnac2H and 17Fnac2H with either ZnEt2 or Cp*2Zn gave homoleptic ZnII complexes (16Fnac2)2Zn (4) and (17Fnac2)2Zn (5), respectively. 1–5 were characterized by IR and NMR spectroscopy (1H, 13C, 19F), elemental analysis and single‐crystal X‐ray diffraction.

Reactions of Rnac2ZnEt (R = Mes, Dipp) and 16Fnac2ZnEt with [Ph3C]­[B­(C6F5)4] simultaneously proceed with β-hydride elimination and ethyl abstraction and formation of the corresponding zinc cations [Rnac2Zn]+ and [16Fnac2Zn]+. While [Rnac2Zn]+ cations undergo additional side reactions but do not react with the [B­(C6F5)4]− anion, [16Fnac2Zn]+ activates the borate anion with formation of 16Fnac2ZnC6F5 (1). In contrast, [16Fnac2Zn]­[SbF6] (2) was formed in the reaction of 16Fnac2ZnEt with [Ph3C]­[SbF6] in SO2. 2 reacts with OPEt3 with formation of [16Fnac2Zn­(OPEt3)]­[SbF6]2 (3) and with B­(C6F5)3 with formation of 1. [16Fnac2Zn]­[SbF6] is slightly less Lewis acidic in comparison to B­(C6F5)3 according to the Gutmann–Beckett method.

Heteroleptic Zn(i) complexes Cp*Zn–Zn(N(R)C(Cp*)O) with η4-coordinated tethered Cp* ligand represent snapshots of isocyanate insertion reactions into Zn–Cp* bonds. Their bonding nature was analysed by single crystal X-ray diffraction and computational calculations.

Dedicated to Prof. H. Schnöckel on the occasion of his 80th birthday.Complexes LZnR (L = C 6 F 5 NC(CF 3 )C(H)C(CF 3 )O; R = Me 1; Et 2) and L 2 Zn(thf) 2 (3) were synthesized and analyzed by NMR ( 1 H, 13 C, 19 F) and IR spectroscopy, elemental analysis, and single crystal X-ray diffraction. Complexes 1 and 2 are dinuclear in the solid state but monomeric in toluene solution according to diffusion-ordered spectroscopy (DOSY-NMR). They showed poor activity in the ring opening polymerization (ROP) of lactide (LA) but moderate activity in the presence of benzyl alcohol (BnOH), yielding polymers with high number average molecular weight (M n ) and moderately controlled molecular weight distribution (PDI). Homonuclear-decoupled 1 H NMR analysis of polylactic acid (PLA) obtained from rac-LA showed isotactic enrichment of the polymer microstructure, and kinetic studies of the ROP of L-LA with complex 2 showed a first order dependence of the monomer concentration. Analyses of low molecular weight polymers by 1 H NMR and MALDI-ToF mass spectrometry demonstrated the coordination-insertion mechanism (CIM).

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