Synthesis and characterization of new, modified terphenyl ligands: Increasing the rotational barrier for flanking rings

ipso-and para-Functionalization of meta-terphenyl ligands with substituted methyl groups: Unusual head-to-tail coupling of terphenyl moieties

“…The angles C(1)-C(2)-C(8) in 5 and C(1)-C(2)-C(6) in 6 are 121.9(3)°a nd 122.55(2)°, being comparable to the angle in a similar terphenyl iodide species having the same structure as 5, only lacking the para methyl on the central phenyl [28]. The angles C(2)-C(1)-I(1) in 5 and 6 are 118.7(3)°and 118.79(1)°, being also similar to other known angles in similar molecules [27].…”

“…In both cases, the NMR spectra displayed proton and carbon signals in the expected regions [35] and no particular characteristics were observed. The slight differences noted in chemical shifts of 7 and 8 when compared to the parent terphenyl iodides 5 and 6, respectively, follow the same trend observed in other related examples of terphenyl iodides [27]. Table 1 Selected bond distances (Å ) and angles (°) for 2, 5 and 6 Table 2 Selected bond distances (Å ) and angles (°) for compound 4 (17) …”

“…The carbon-iodine distances are 2.111(4) and 2.115(3) Å for 5 and 6, respectively. Bond lengths in similarly crowded terphenyl iodides vary between 2.106(2) and 2.111(2) Å [27]. The slight elongation of the carbon-iodine bond in 5 and 6 may be attributable to both the inductive electron-donating effect of the methyl group in para position on the central ring and to the same effect of isopropyl groups on the flanking aryls.…”

Tuning Main Group Redox Chemistry through Steric Loading: Subvalent Group 13 Metal Complexes of Carbazolyl Ligands

“…Thermal ellipsoids set at the 40 % probability level; four toluene solvate molecules lying outside of standard Van der Waals contact distances from Tl(1), and hydrogen atoms omitted (and tBu groups shown in stick representation) for clarity Key bond lengths [] and angles [8]: Tl(1)ÀN (2) ed for Ga 2 X 3 (X = Br, I). [21] The InÀIn distance measured for 5 is similar to that measured for the dianionic component of [In 2 A C H T U N G T R E N N U N G {In 2 …”

“…[1,2] In particular, phenyl ligands bearing bulky alkyl or aryl substituents in the 2-and 6-positions (I; Scheme 1), which were pioneered principally for main-group-metal systems, [3] have more recently been exploited in the synthesis of landmark multiplybonded transition-metal compounds, such as Powers CrÀCr quintuple bond. [4] Such species have been of interest not only from a fundamental structure/bonding perspective (e.g.…”