A New Type of Asymmetric Tridentate Pyrrolyl-Linked Pincer Ligand and Its Aluminum Dihydride Complexes

Abstract

The new pyrrolyl-linked pincer-type ligand, [C(4)H(2)NH(2-CH(2)NH(t)Bu)(5-CH(2)NMe(2))] (1), that has been employed conveniently in high yield by treatment of (2-t-butylaminomethyl)pyrrole with 1 equiv of formaldehyde and dimethylamine hydrochloride each in diethylether and its corresponding aluminum derivative, [C(4)H(2)N(2-CH(2)NH(t)Bu)(5-CH(2)NMe(2))]AlH(2) (2), that has been generated from Me(3)N.AlH(3) using diethylether as a solvent are described. Furthermore, reactions of 2 with 2 equiv of either 1,3-diphenylpropane-1,3-dione in diethylether or phenyl thioisocyanate in dichloromethane interestingly formed [C(4)H(2)N(2-CH(2)NH(t)Bu)(5-CH(2)NMe(2))]Al(PhCOCHCOPh)(2) (3) and [C(4)H(2)N(2-CH(2)NH(t)Bu)(5-CH(2)NMe(2))]Al(SCHNPh)(2) (4), respectively, following deprotonation or hydroalumination reaction kinetics under a dry nitrogen environment. All of the compounds have been subjected to the X-ray diffraction technique in the solid state as well as characterized by NMR spectra.

Preparation of aluminum(III) (bis(amido)pyridine)(thiolate) complexes: Unexpected transmetalation mediated by LiAlH4

“…These Al III -N bonds are significantly shorter than the Zn II -N (2.202(2); 2.173(2) Å) and Fe II -N (2.188(2); 2.184(2) Å) bond lengths observed in 1 and [Fe II (LN 3 S)(OTf)], respectively [27], or the Al III -N(H)RR’ bond lengths of 2.090(5) and 2.098(5) Å seen in the complex [(( R , R )-R 4 -salcyan)Al(OH)] [36], where the amine donor is protonated. Furthermore, the Al III -S distance in 2a (2.2798(9) Å) falls in the reported range for other Al III -SR bond lengths (2.220(1) to 2.5226(6) Å) [37–39]. …”

Molecular Main Group Metal Hydrides

“…As with carbon-supported aluminum hydride systems, a common reactivity pathway is the hydroalumination of organic π-bonds. Given the plethora of new N -donor aluminum hydride systems reported in the past two decades, ,− this section will aim to focus on the new bonding motifs and reactivity pathways uncovered in this area.…”

Synthesis and structures of tantalum chloride and tantalum aryloxide compounds bearing bidentate and tridentate pyrrole‐amine ligands

“…[C 4 H 2 NH‐2,5‐(CH 2 NMe 2 ) 2 ], [C 4 H 3 NH‐2‐(CH 2 NEt 2 )] and [C 4 H 2 NH‐2‐(CH 2 NMe 2 )‐5‐(CH 2 NH t Bu)], and their corresponding lithium salts are synthesized according to the published literature. [ 36–43 ] CDCl 3 was degassed by using freeze‐and‐thaw cycles and dried over 4 Å molecular sieves. Proton nuclear magnetic resonance ( 1 H NMR) and carbon‐13 nuclear magnetic resonance ( 13 C NMR) spectra were collected on a Bruker AC300 instrument.…”