Synthesis of the bulkym-terphenyl phenol Ar*OH (Ar* = C₆H₃-2,6-Mes₂, Mes = 2,4,6-trimethylphenyl) and the preparation and structural characterization of several of its metal complexes

Abstract

The bulky m-terphenyl phenol Ar*OH 1 (Ar* = C6H3-2,6-Mes2, Mes = 2,4,6-trimethylphenyl) was synthesized via the treatment of Ar*Li with nitrobenzene. The phenol 1 is prepared in modest to good yield using this method. Attempts were also made to prepare 1 through oxidation of the bulky boronic acid Ar*B(OH)2 with Oxone®, but this reaction was not suitable for preparative-scale reactions. Side products of the reaction between Ar*Li and nitrobenzene were identified as Ar*[N(O)Ph] and [C6H5N(O)]2 and were characterized by X-ray crystallography and EPR spectroscopy. A variety of main-group and transition-metal complexes of Ar*OH were prepared, namely Sn(OAr*)2, Ge(OAr*)2, [N(SiMe3)2]Ge(OAr*), [Me2Al(OAr*)]2, and Ti(NMe2)(OAr*)2. All compounds were characterized spectroscopically and most were studied by single-crystal X-ray diffraction as well.Key words: m-terphenyl, main-group compounds, X-ray crystallography, multinuclear NMR spectroscopy, EPR spectroscopy.

Dispersion Forces and Counterintuitive Steric Effects in Main Group Molecules: Heavier Group 14 (Si–Pb) Dichalcogenolate Carbene Analogues with Sub-90° Interligand Bond Angles

“…Previous work by Clyburne to determine a structure for the complex Ge(OAr Me 6 )2 proved unsuccessful due to poor crystallinity although a structure of Sn(OAr Me 6 )2 was obtained. 31 An overview of the synthesis of 2-20 is given in Scheme 1. 25° C over a period of several months.…”

The role of the bis-trimethylsilylamido ligand, [N{SiMe3}2]−, in main group chemistry. Part 2: Structural chemistry of the metallic p-block elements

“…Despite examples of other two-coordinate heteroleptic species being reported (e.g. Ge(OAr*)(N{SiMe 3 } 2 ) (61), where Ar* = 2,6-(mes) 2 C 6 H 3 ) [65], most of the chemistry that has been developed in the subsequent 40 years has focused on the original 'Lappert' germylene 60.…”

“…The related benzil derivative, Ge(N{SiMe 3 } 2 ) 2 (C 2 Ph 2 O 2 ) (63) was structurally characterized as the Ge(IV) adduct with the reduced form of the ligand [Ph(O)C = C(O)Ph] 2− [67]. The tris-amide Ge(N{SiMe 3 } 2 ) 3 Br (64) was originally reported in 1987 from the insertion of 60 into the N Br bond of BrN{SiMe 3 } 2 [68]; the crystal structure of 64 and of the n-Bu derivative, Ge(N{SiMe 3 } 2 ) 3 (nBu) (65) were reported more recently [69]. The insertion of 60 into phosphorus-chlorine bonds of Ph 2 PCl and t-BuPCl 2 afforded the corresponding Ge(IV) phosphanide compounds Ge(PPh 2 )(N{SiMe 3 } 2 ) 2 Cl (66) and Ge(Pt-BuCl)(N{SiMe 3 } 2 ) 2 Cl (67), respectively [70].…”

Synthesis and structural characterization of bulky m-terphenyl benzyl alcohols and a tricoordinate zinc complex

“…This property is perhaps best exemplified by the work of Power and colleagues [1], who have prepared a number of unprecedented main group and transition metal complexes by attaching the m-terphenyl ligand directly to the metal centers through the C 1 carbon. 68 Instead of direct metal-carbon coordination, our interests have focused on placing a variety of functional groups, including amidines [2], boronic acids [3], carboxylic acids [4], and Schiff bases [5] in the central position of the m-terphenyl and using those sites to bind metals. This introduces an extra degree of freedom to the coordination sphere and allows for the possibility of chelating or bridging interactions between the metal and the m-terphenyl ligand.…”