Reversible Ethylene Cycloaddition Reactions of Cationic Aluminum β-Diketiminate Complexes

Lutetium‐Methanediide‐Alkyl Complexes: Synthesis and Chemistry

“…The process might experience the following steps: 1) insertion of two molecules of Ph 2 C=O into Lu-C alkyl bonds to generate metal alkoxyl species; 2) one Ph 2 C=O transannular addition to the six-membered metallocycle accompanied by nitrogen disassociation from the metal center, similar to the 1,4-cycloaddtion of O 2 , CH 2 =CH 2 and CO 2 etc. to the "nacnac" framework; [16] 3) insertion of the lutetium oxygen bond Ln-m 2 -O to Ph 2 C=O afforded the lutetium diphenylmethane diolate species, which, to our knowledge, is an unprecedented example of the rareearth metal oxo bond Ln-m 2 -O insertion into an unsaturated organic molecule. [17,18] Due to the poor crystal data for complex 4, a detailed metrical discussion is not provided but the data confirm the chemical connectivity.…”

Dimethylaluminum complexes bearing a chiral diketiminate ligand: Synthesis, characterization and ring-opening polymerization of ε-caprolactone

“…2, the aluminum center in R,R-1 is surrounded by two nitrogen atoms of the chiral nacnac ligand and two methyl groups, exhibiting distorted tetrahedral geometry. The N(1)\Al (1)\N(2) angle (94.96(6)°) and C (22)\Al (1)\C(23) (2)) [16], [(2,6-iPr 2 C 6 H 3 NCMe) 2 HC] AlMe 2 (B) (96.18 (9)°; 117.4(1)) [16,20], or [(2,6-iPr 2 C 6 H 3 4-ClC 6 H 4 N 2-C 2 Me 2 )HC]AlEt 2 (C) (94.50 (7)°; 115.59(11)°) [10c]. The deviation of the aluminum center from the ligand backbone N1\C2\C3\C4\N2 is 0.85 Å, which is larger than those in the above mentioned complexes A (0.33 Å), B (0.72 Å) and C (0.56 Å) with aryl-substituted nacnac ligands.…”

(C7H13N2)3Al − The First Tris(diketiminato)metal Complex

“…Owing to the increased coordination number, the geometry of the VinAl fragments exhibits a significant difference to that found for 2 and 3 (X ϭ BPh 4 ) due to a lengthening of the AlϪN bonds and a decrease in the NϪAlϪN bond angles [AlϪN 2.002(18) to 2.0626(17) Å , NϪAlϪN 86.19 (7) to 91.39(7)°]. There is no indication of steric overcrowding, for example by distortion of the near planar ring fragments or by unusual lengthening of bonds.…”