Inserted products of lithium silylquinolylamide dimers [{8-(2-R-C₉H₅N)N(Me₃Si)}Li·OEt₂]₂ (R = H or Me) with dimethylcyanamide and their reactive derivatives with metal halides

Abstract

The insertion reactions of lithium silylquinolylamide dimers [{8-(2-R-C9H5N)N(Me3Si)}Li·OEt2]2 (R = H, 1a; R = Me, 1b) with dimethylcyanamide afforded dimeric lithium 8-quinolylguanidinates [{8-(2-R-C9H5N)NC(NMe2)N(SiMe3)}Li]2 (R = H, 2a; R = Me, 2b) with a cisoid arrangement of the ligands. Further reaction of 2b with MCl2 (M = Co or Fe) formed the eight-membered binuclear metallic 8-quinolylguanidinate complexes [{8-(2-CH3-C9H5N)NC(NMe2)N(SiMe3)}MCl]2 (M = Fe, 3; Co, 4). The reaction of 2a with (MeC5H4)TiCl3 afforded a centrosymmetric dimeric titanium(IV) complex [{8-(C9H6N)NC(NMe2)N}Ti(MeC5H4)Cl]2 (5) via a metathesis reaction and the elimination of SiMe3Cl. The guanidinate ligand 2b was hydrolyzed with an equimolar amount of water, and reacted with (MeC5H4)TiCl3 forming a monoligated half-titanocene compound {8-(2-CH3-C9H5N)N(H)C(NMe2)N}Ti(MeC5H4)Cl2 (6). Therefore lithium silylquinolylamide dimers provided various coordinative multi-dentate ligands and resulted in a family of metal complexes.

Lithium Quinolyl‐Amidinates Efficiently Promoting Ring‐Opening Polymerization of ε‐Caprolactone: Synthesis and 7Li NMR Spectroscopic Studies

“…The molecule consists of two sets of two four‐membered rings and one five‐membered ring‐fused framework, whereas these rings are fused in a tub shape (i.e., open box); that is, two tubs are fused in reverse (i.e., back to back) (Figure ) . The Li1–N1 bond lengths in complex Li2 [Li1–N1 = 2.016(3) Å] and complex Li3 [Li1–N1 = 2.018(4) Å] are shorter than the Li1–N5 bond lengths in Li2 [Li1–N5 = 2.315(4) Å] and Li3 [Li1–N5 = 2.195(4) Å], respectively.…”

Aluminum chelates supported by β-quinolyl enolate ligands: synthesis and ROP of ε-CL

“…1.7362( 12) Al(1)-O(3) 1.8236( 11) Al(1)-O(3) i 1.9141( 11) Al(1)-N(1) 2.0487( 14) O(1)-C (11) 1.304(2) C(10)-C( 11 molecular weight of the resultant PCL from the theoretical value and the broadened PDI (Table 3, entries [13][14][15][16]. With an increase of BnOH to 8 equiv., the monomer conversion was slower (Table 3, entry 17).…”

“…12 We have reported that the insertion reaction of lithiated picoline with nitriles gives [N,N] β-diketiminato complexes 13 and lithium quinolylamide with nitriles affords quinolylguanidinates. 14 With this in mind, we decided to explore the preparation of aluminum derivatives coordinated by bidentate quinolylenolate ligands and to mediate as a catalyst in the polymerization of cyclic esters. In this contribution, we report the synthesis and characterization of some novel aluminum complexes containing differently substituted β-quinolyl enolate [N,O] ligands, and develop their applications for the ROP of ε-CL.…”

Synthesis, mechanism and ethylene polymerization catalysis of Ge(iv), Sn(ii) and Zr(iv) complexes derived from substituted β-diketiminates

“…9 Our group demonstrated that lithium silylquinolylamide reacted with (MeC 5 H 4 )TiCl 3 afforded a titanium(IV) complex [{8-(C 9 H 6 N)NC(NMe 2 )N}Ti(MeC 5 H 4 )Cl] 2 via a metathesis reaction and the elimination of SiMe 3 Cl. 10 Apparently, in the presence of stronger Lewis acid, the formation of new metal-amido bond was thermodynamically favored by elimination of SiMe 3 Cl.…”