Functionalization of sterically hindered o-benzoquinones: amino-substituted 3,6-di(tert-butyl)-o-benzoquinones

Lanthanide‐Based Dinuclear Complexes Involving an o‐Quinone–Tetrathiafulvalene–o‐Quinone Bridging Ligand: X‐ray Structures, Magnetic and Photophysical Properties

“…The ligand L is planar, and the C15=C15 i central bond length of 1.380(30) Å attests the neutral form of L in 6. In fact, this average value is similar to the lengths of the C=O bonds in neutral L (1.218 Å) [11] and other o-benzoquinones (1.21-1.22 Å), [16] whereas it is shorter than the one and half C-O bonds of o-semiquinone radical anions (1.28 Å). The dinuclear complex 6 is very similar to 4 and 5, and the significant difference between the three complexes -the greater size of the voids in the structure of 6 compared with that in 4 and 5 -is due to the small size of the Yb III ion.…”

o-Semiquinonato and o-iminosemiquinonato rhodium complexes. EPR study of the reactions in coordination sphere of rhodium

“…3b) is caused by interaction of unpaired electron with two nitrogen nuclei a i (2N) = 0.35 G and four protons of piperazine bicycle a i (4H) = 1.10 G. Hyperfine coupling constants were obtained by simulation as well. Observable splitting only on four methylene protons of eight ones is caused by rigid configuration of piperazine substituent in contrast to previously described glycol one [7]. Scheme 2 represents the spatial configuration of piperazine substituent as a result of molecular modeling (''HyperChem'' 8.0.3).…”

Geometrical and energetical aspects of structure of 3,6-di-tert-butyl-o-benzoquinones

“…Experimental procedure 4,7-Di-tert-butyl-5,6-dihydro-1,3-benzothiol-2,5,6-trione (1), 5,8-di-tert-butyl-2,3-dihydro-1,4-ethanoquinoxaline-6,7-done (2), 5,8-di-tert-butyl-2,3-dihydro-1,4-benzodioxine-6,7-dione (3), 3,6-di-tert-butyl-4,5-dimethoxycyclohexa-3,5-diene-1,2-dione (4), 3,6-di-tert-butyl-o-benzoquinone (5) were prepared according to the reported procedures [8,9,[17][18][19][20][21]. Commercial benzene was purified according to standard laboratory procedures [22].…”