Reactions of an Aluminum Amide with Aromatic Nitriles: Formation of Al−N−C Frameworks

Abstract

Reactions of a four-membered Al−N ring, [(Dipp)HNAlMe2]2 (2; Dipp =2,6-diisopropylphenyl), with the aromatic nitriles PhCN, TbpCN (Tbp =4-tert-butylphenyl), DmpCN (Dmp = 2,6-dimethylphenyl), DepCN (DepCN = 2,6-diethylphenyl), and DippCN are reported. 2 reacts with PhCN to give a 1:2 insertion product, the tetrameric aluminum amidinate 3, whereas with TbpCN it gives the 1:1 insertion products 4−6. Under similar conditions, DmpCN, DepCN, and DippCN do not undergo insertion but form simple adducts of alumazene (1), 7a−c and 8a−c (2:1 and 1:1 nitrile/alumazene), in which the nitriles coordinate to Al. Compounds 3−6 and 7a−c have been structurally characterized. 3 is comprised of four four-membered aluminum amidinate rings. 5 features a core made of three Al2N2 and two AlCN2 four-membered rings fused together. The structures of 4 and 6 consist of a dimer of a six-membered Al2CN3 framework. A high-yield synthesis of 3 from N-(Dipp)benzamidine and AlMe3 has also been reported.

Zinc(II) complexes of Triaza and Amidinate ligands: Efficient initiators for the ring‐opening polymerization of ε‐Caprolactone and rac‐Lactide

“…The Zn1‐N2 bond (2.054(3) Å), which is exocyclic to the four‐membered chelate ring, is significantly shorter than the endocyclic Zn1‐N1 bond (2.206(3) Å). Similar observation was made in tetrameric aluminium amidinates reported by our group recently . The bond angle of O(1)‐Zn(1)‐N(1), which is 60.72(9) Å, is almost half of the other bond angles found around the metal.…”

“…ε ‐Caprolactone, purchased from Acros Organics, was stirred over calcium hydride for 24 h and distilled under vacuum. N ‐(Dipp)‐benzamidine and N ‐phenylbenzamidine were prepared by following literature procedures . Hexane and toluene (from Na/benzophenoneketyl) were distilled fresh as and when required.…”

From polygons to polyhedra through intermediate structures. A shape measures study of six-atom inorganic rings and clusters

“…4), the 16 skeletal electrons in this case result in an allylic N-S-N group 4a with S-N distances of 1.56 Å, compared to 1.68 Å of the other two N-S bonds. Similarly, in the family of 34-electron alazanes with Al 3 N 3 rings and general formula (LAlR) 2 (AlR) (NR) 3 we find the envelope 58,59 and boat 60 (4b) conformations, with RN-Al(R)-NR allylic groups in both cases and distortions along the respective paths of 19-20%. Several bicyclic compounds of type 5 have been reported with a variety of p-block elements in the corners: B, Ga, Si, Ge, Sn, N, Bi and O.…”

Alumazene Reactivity with Quinolinols – Addition and Substitution Reactions on the Al3N3 Ring

“…5,6,38 Previous reactions of alumazene (1) were designed as reactions with N-or O-bases. [7][8][9][10] In the present case we use the ligands with the N-donor site and the acidic OH group. The proton is transferred to alumazene imidic nitrogen.…”

“…Several types of mono-, bis-, and trisadducts were reported in the literature. [7][8][9][10][11] Stepwise fluorination of alumazene 1 by Me 3 SnF or by BF 3 represents metathesis reactivity leading to the substitution of the methyl groups on aluminium. 12 Dealkylsilylation reactions of 1 with trimethylsilyl esters of sulfonic, phosphoric, and phosphonic acids are another type of alumazene reactivity.…”