Synthesis and Complexation Behavior of Indenyl and Cyclopentadienyl Ligands Functionalized with a Naphthyridine Unit

Abstract

Lithium indenide (Li-Ind) or cyclopentadienide (Li-Cp) derivatives react as nucleophiles with 8-(methylsulfinyl)-1,5-naphthyridine (Naph), leading to donor-functionalized ligands IndNaph or CpNaph, respectively. The new ligands comprise two N-donor atoms, which, for geometric reasons, cannot bind to the same metal atom. In complexes, where the metal atom is bound by the Cp or Ind moiety, the N5-donor atom is located in a distal position. The coordination behavior to Rh or Zr metal centers has been investigated. The Cp-based ligands show the expected chelating coordination mode with η5-Cp and N coordination, whereas the indenyl units act as dihapto, trihapto, or pentahapto ligands. The dinuclear Rh­(I) complex 12 shows a rare coordination geometry with two η3 ligands bridging a Rh2(CO)3 fragment.

BF3·SMe2 for Thiomethylation, Nitro Reduction and Tandem Reduction/SMe Insertion of Nitrogen Heterocycles

“…As a result, significant effort has been invested in developing synthetic methods for the preparation of these compounds. The classical method for installing a thioether moiety on an electron deficient aromatic substrate is via an S N Ar using thiolate salts as the nucleophile . Although thiolate salts are good nucleophiles, these types of reagents suffer from a range of drawbacks including volatility, instability, toxicity, and strong, unpleasant odors .…”

Synthetic Strategies, Reactivity and Applications of 1,5-Naphthyridines

“…Given that the halide group is a good leaving group, halo-1,5-naphthyridine derivatives are very interesting intermediates for the introduction of nucleophilic reagents in the 1,5-naphthyridine ring and may be prepared by halogenation of hydroxyl-1,5-naphthyridines. For example, the 1,5-naphthyridine derivatives were prepared [ 61 ] and converted into the corresponding 2-chloro derivative 71a using phosphorus oxychloride with 1,5-naphthyridine-2(1 H )-one 70a ( Scheme 26 ) [ 62 ], and has been used for synthesis of 1,5-naphthyridine functionalized indenyl and cyclopentadienyl ligands. The same strategy has been used for the preparation of chloro-1,5-naphthyridine derivative 71b ( Scheme 26 ) [ 15 ].…”

“…The synthesis of 1,5-naphthyridine functionalized indenyl and cyclopentadienyl ligands containing sulfur substituents has been carried out by treatment of chloro derivative 72a (previously prepared, vide supra, Scheme 27 ) with sodium methanethiol in the presence of NaH to furnish the methylsulfanyl derivative 106a ( Scheme 39 ) [ 62 ]. Similarly, the nucleophilic substitution of 72a with led to 2-methylpropane-2-thiol 106b ( Scheme 39 ) with a moderate yield.…”

Synthesis of Novel Trichloride Indenyl Zirconium Complexes with Pendant Pyridine Moiety

“…2); 而三(二甲胺基) 一茚锆若与 3 equiv.的 Me 3 SiCl 也可以得到取代的单茚 锆络合物 [8,14] . 这种方法适用于环戊二烯或茚基配体上 有较大取代基, 但原料 Zr(NMe 2 ) 4 制备比较困难.…”

“…r.t. [24] . 另外中心金属 Zr 与四 氢呋喃上的氧原子也配位, Zr-O 键长为: 2.373(2) Å, 与文献报到类似化合物 Zr-O 配位键平均键长 2.350 Å 接近 [8,17] . 中心金属 Zr 到茚环五元环上各个碳原子的距 离不等, 分别是: …”