New Insights into the Structures of Diorganotellurium Oxides. The First Polymeric Diorganotelluroxane [(p-MeOC₆H₄)₂TeO]_n

Abstract

The characterization of the previously reported diorganotellurium oxides R 2 TeO (R ) Ph (1) and p-MeOC 6 H 4 (2)) was revisited by osmometric molecular weight determinations, 125 Te NMR spectroscopy, and electrospray spectrometry (ESMS) in solution and by 125 Te MAS NMR spectroscopy in the solid state. The single-crystal X-ray structure of 2 revealed a polymeric arrangement that features a zigzag configured Te-O backbone without any secondary Te‚‚‚O interactions. In solution 1 and 2 exist predominantly as monomers but appear to be in equilibrium with higher oligomers to a minor extent.

Intramolecularly Coordinated Telluroxane Clusters and Polymers

“…The average Te À O bond length of 1.97(1) is slightly shorter than the average single bond lengths observed for polymeric [(4-MeOC 6 H 4 ) 2 TeO] n (2.063(2) ) [12] (1)8). [13] The Te1 À Cl1 and Te2 À Cl4 bond lengths of 2.551(5) and 2.562(5) are slightly longer than the Te1 À Cl2 and Te2 À Cl3 bond lengths of 2.470(5) and 2.479(4) , respectively.…”

“…The TeÀO bond lengths cover a large range from 1.902(3) to 2.243(3) , with the average of 2.027(3) being close to the average single bond length of polymeric [(4-MeOC 6 H 4 ) 2 TeO] n (2.063(2) ). [12] Interestingly, the Te···Cl bond length of 3.051 (8) is significantly longer than the average values of 2 (2.486(2) ) and 3 (2.516 (5) ), which suggests that the Te···Cl bond is rather ionic. Compound 5 is Scheme 4.…”

“…The base hydrolysis of 2 provided the novel (7) depending on the reaction conditions applied. The reaction of 7 with ClTeA C H T U N G T R E N N U N G (OiPr) 3 in the presence of water gave rise to the telluroxane (8-Me 2 NC 10 H 6 Te) 6 Te 2 O 12 Cl 2 (8). The crystal and molecular structures of 1-3 and 5-8 were determined by X-ray crystallography.…”

Well‐Defined Stibonic and Tellurinic Acids

“…[9] These observations prompted us to study the structures of archetypal stibonic and tellurinic acids that are kinetically stabilized by a bulky m-terphenyl substituent. The kinetically controlled hydrolysis under basic conditions (in a two-layer system of toluene and 0.1m aqueous sodium hydroxide) of 2,6- [10] Given that reaction conditions were similar in both studies, it appears that the Sb V À C bonds are more resistant towards hydrolysis than the Sb III À C bonds of the same mterphenyl substituent.…”

Eine wohldefinierte zweikernige Telluronsäure [RTe(μ‐O)(OH)3]2

“…Dies gelang schließlich durch die Synthese eines kinetisch stabilisierten Prototyps in zwei einfachen Syntheseschritten (Schema 1). Zunächst wurde die zweikernige m-Terphenyltellurinsäure 1 [6] mit Natriumhydrid zum vierkernigen Natrium-m-terphenyltellurinat Na 4 (2,6-Mes 2 C 6 H 3 Te) 4 (m 3 -O) 8 [7] Die räumliche Anordnung der kristallographisch äquivalenten Te-Atome von 2 ist verzerrt tetraedrisch, wenn man die primäre Koordinationsphäre (O 2 C-Donorsatz) und das stereochemisch aktive freie Elektronenpaar betrachtet. Die Te-OBindungen sind mit 1.832(4) und 1.850(4) signifikant kürzer als die durchschnittliche "Standard-Te-O-Einfachbindung" in [(4-MeOC 6 H 4 ) 2 TeO] n (2.063(2) ) [8] und deuten auf eine formale Bindungsordnung von 1.5 hin.…”