Syntheses of {(MeC₅H₄)₂Ln(THF)[O CN(i-Pr)₂ NPh]} (Ln = Y, Er, Yb) and the X-ray Crystal Structure of the Yttrium Complex:  The Active Species for Polymerization of Phenyl Isocyanate by (Diisopropylamido)bis(methylcyclopentadienyl)lanthanides

Abstract

Insertion of phenyl isocyanate into the Ln−N σ bond of (MeC5H4)2Ln(i-Pr)2(THF) (Ln = Y (1), Er (2), Yb (3)), which were synthesized by reactions of (MeC5H4)2LnCl(THF) with LiN(i-Pr)2, led to the isolation of {(MeC5H4)2Ln(THF)[O CN(i-Pr)2 NPh]} (Ln = Y (4), Er (5), Yb (6)). The latter is the active species for phenyl isocyanate polymerizations. The X-ray structure analysis of 4 shows that Y is coordinated to two methylcyclopentadienyl groups and one bidentate anion [O CN(i-Pr)2 NPh]- via a partial single bond, partial donor bond interaction with N1 and O1 atoms.

Synthesis and molecular structures of lanthanocene amide complexes and their catalytic activity for addition of amines to nitriles

“…The coordination number of central metal for each complex is eight. The solidstate structures of I-III are quite similar to those for lanthanocene amides reported previously [10,12].…”

“…The Ln-N bond lengths of 2.206(9) Å for I, 2.188(3) Å for II and 2.241(4) Å for III fall into the range of Yb-amide and Y-amide bond lengths, respectively (2) 130.252 (27) 129.019 (12) 129.770 (17) Cent (1) is the centroid of the C(1)-C(5) ring and Cent (2) is the centroid of the C (7) To further assess the influence of amide group on the reactivity, a known aliphatic amide complex (CH 3 C 5 H 4 ) 2 YbN i Pr 2 (THF) IV was also prepared by the published method [12].…”

“…For example, lanthanide amides are active catalysts for a variety of olefin and alkyne transformations, including hydroamination/cyclization [1,2], hydroalkoxylation/cyclization [3], ethylene polymerization [4,5], hydrosilylation [6], the addition of terminal alkynes to nitriles [7], the monocoupling reaction of isocyanides with terminal alkynes [8]. They are also found to be the catalysts for the polymerization of polar monomers, such as methylmethacrylate [9][10][11], phenylisocyanate [12], e-caprolactone and lactide [13,14], as well as for the Tishchenko reaction [15,16], guanylation of amines with carbodiimides [14], amidation of aldehydes with amines [17], and Mannich-type reaction [18]. etc.…”

Synthesis, structure and reactivity of samarium complexes supported by Schiff-base ligands

“…Lanthanide complexes were reported to serve as the catalyst for polymerization of alkyl isocyanate [48] and alkyl isocyanates are well-known to be able to insert into Ln-C, Ln-N and Ln-S bond to give the corresponding insertion products [49][50][51]. Thus, the reaction of complex 3 with phenyl isocyanate in 1:1 molar ratio was tried.…”

The salt-free diamido complexes of lanthanide supported by β-diketiminate: Synthesis, characterization, and their catalytic activity for the polymerization of acrylonitrile and ε-caprolactone

“…The organolanthanide amide has been found to be the important precatalysts in a variety of homogeneous catalysis, including hydroamination of alkyne and alkene and the polymerization of polar monomers [1][2][3][4][5]. However, almost all of the work focused on the complexes with a dianionic ancillary ligand and one amido group.…”