33332-61-5Relevant academic research and scientific papers
Rapid synthesis of new discotic liquid crystals based on diquinoxalino[2,3-a:2′,3′-c]phenazine containing hexakis(alkoxy) side arms
Ong, Chi Wi,Liao, Su-Chih,Chang, Tsu Hsing,Hsu, Hsiu-Fu
, p. 1477 - 1480 (2007/10/03)
The condensation of 1,2-bisalkoxy-4,5-diaminobenzene 2a-e derivatives with freshly prepared hexaketocyclohexane give hexakis(alkoxy)diquinoxalino[2,3-a:2′,3′-c]phenazines in good yield. DSC and polarization microscopy showed HATOC6 has both the crystalline (K) to mesophase (M) and the mesophase (M) to isotropic (I) phase transitions. Importantly, the alkoxy substituted compound synthesized showed an M-I transition because of greater stability, whereas the reported alkyl-thiol decomposes after the mesophase.
Acetoxylation of 6,7-dialkoxy-substituted 1,4-dihydroquinoxaline-2,3-diones (QXs) using fuming nitric acid in acetic acid: A facile synthesis of 5-acyloxy-6,7-dialkoxy QXs
Zhou, Zhang-Lin,Weber, Eckard,Keana, John F. W.
, p. 7583 - 7586 (2007/10/02)
Treatment of 6,7-dialkoxy-1,4-dihydroquinoxaline-2,3-diones 3 with fuming nitric acid in acetic acid at 25°C resulted in an acetoxylation reaction, giving 5-acetoxy-6,7-dialkoxy-1,4-dihydroquinoxaline-2,3-diones 4 in moderate yields. A mechanism involving ipso attack of nitronium ion as the first step is proposed.
