Metal based synthetic routes to heavy alkaline earth aryloxo complexes involving ligands of moderate steric bulk.

نویسندگان

  • Glen B Deacon
  • Peter C Junk
  • Graeme J Moxey
  • Marites Guino-o
  • Karin Ruhlandt-Senge
چکیده

Treatment of an alkaline earth metal (Ca, Sr, Ba) with 2,4,6-trimethylphenol (HOmes) at elevated temperatures in the presence of mercury under solvent-free conditions, followed by extraction of the reaction mixture with 1,2-dimethoxyethane (dme), afforded dinuclear alkaline earth aryloxo complexes [Ae2(Omes)4(dme)4] (Ae = Ca 1, Sr 3, Ba 6). Extraction of the Ca metal and HOmes reaction mixture with thf afforded [Ca3(Omes)6(thf)] 2. In contrast, redox transmetallation ligand exchange reactions between an alkaline earth metal, diphenylmercury and HOmes in dme yielded solely 1 for Ca metal, a mixture of 3 and the methoxide bridged cage [Sr5(Omes)5(OMe)5(dme)4] x 2dme 4 for Sr metal, and solely [Ba5(Omes)5(OMe)5(dme)4] x dme 7 for Ba metal. The methoxide ligands originate from the C-O activation of the dme solvent. Treatment of liquid ammonia activated Sr or Ba metal with HOmes in thf afforded the linear species [Ae3(Omes)6(thf)6] (Ae = Sr 5, Ba 8), and 8 was also obtained from barium metal and HOmes in refluxing thf. The structures of 1 and 3, determined by X-ray crystallography, consist of two six coordinate Ae metal atoms, to each of which is bound a terminal aryloxide ligand, two bridging aryloxide ligands, and chelating and unidentate dme ligands. The structures of 4 and 7 contain five Ae metal atoms arranged on the vertices of a distorted square based pyramid. The Ae atoms are linked by four mu3-OMe ligands and a mu4-OMe ligand. Four bridging aryloxide ligands and four chelating dme ligands complete the coordination spheres of the four seven coordinate Ae atoms at the base of the pyramid, and a terminal aryloxide ligand is bound to the five coordinate apical Ae atom. The structures of 5 and 8 consist of a trinuclear linear array of Ae metal atoms, and contain solely bridging aryloxide ligands. Three thf ligands are bound to each terminal Ae atom, giving all Ae atoms a coordination number of six.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Voltammetric Study of Cd2+ Complexation with some Compounds of Garlic

The complexation of Cd2+ by diallyl disulfide (DADS) and diallyl sulfide (DAS) has been studied by differential pulse voltammetry. Stability constants, (log β), of the 1:1 (PbL) and 1:2 (PbL2) complexes, where L = ligand, were found to be in the range of ca. 5.8 - 6.2 and 9.6 -10.6, respectively. Complex formation is accompanied with a significant decrease in the peak current and the shift of t...

متن کامل

Bis(phosphinoselenoic amides) as versatile chelating ligands for alkaline earth metal (Mg, Ca, Sr and Ba) complexes: syntheses, structure and ε-caprolactone polymerisation.

We report here a series of heavier alkaline earth metal complexes with N,N'-(ethane-1,2-diyl)bis(P,P-diphenylphosphinoselenoic amide) using two synthetic routes. In the first route, the heavier alkaline earth metal bis(trimethylsilyl)amides [M{N(SiMe3)2}2(THF)n] (M = Ca, Sr, Ba), when treated with phosphinoselenoic amine [Ph2P(Se)NHCH2CH2NHPPh2(Se)] (1), afforded the corresponding alkaline eart...

متن کامل

Isolation and Structural Characterization of Alkali and Alkaline Earth Metal Salts with Synthetic Non Cyclic Ionophores

In the present study, an investigation on the complex formation between mono- and divalent metal ions (Na+, K+, Li+ and Mg2+) in the form of salt with different podands using various solvents has been carried out.  Isolated complexes were characterized by different spectroscopic techniques viz. IR, NMR and elemental analysis. On the basis of ...

متن کامل

The Syntheses and Characterization of Three Novel Macrocyclic Polyether Ligands and Some of Their Alkaline Metal Complexes

The macrocyclic ligands 2,3,5,6-Bis{3’-bromo-5’-tert-butyl benzo-5-phenyl benzo} 12C3 (L1), 2,3,5,6-bis{3’-bromo-5’-tert butyl-benzo-5’-phenyl-benzo}15C4 (L2), 2,3,5,6-bis{3’-bromo-5’-tert butyl-benzo-5’-phenyl-benzo}18C5 (L3) have been synthesized and their alkaline metal compounds with NaClO4∙H2O and KClO4  have ...

متن کامل

Synthesis of fluoro(aryloxo)alkaline earth metal cages by C-F bond activation.

Treatment of Ca or Sr metal with Hg(C(6)F(5))(2) and 2,4,6-trimethylphenol (HOmes) in 1,2-dimethoxyethane (dme) at room temperature resulted in C-F bond activation, giving rise to the unique fluoro(aryloxo)alkaline earth cages [Ca(5)(mu(4)-F)(mu(3)-F)(4)(mu-Omes)(4)(Omes)(dme)(4)] 1 and [Sr(10)(mu(4)-F)(4)(mu(3)-F)(4)(mu-Omes)(12)(dme)(4)] 2, which can be viewed as arrested fluorite structures.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Dalton transactions

دوره 25  شماره 

صفحات  -

تاریخ انتشار 2009