Heterocycle Annulation of Enolizable Vinyl Quinone Imides. Dihydroquinolines and Quinolines from Thermal 6锜?Electrocyclizations and Indoles from Photochemical Cyclizations was written by Parker, Kathlyn A.;Mindt, Thomas L.. And the article was included in Organic Letters in 2002.Related Products of 74440-80-5 This article mentions the following:
Enolizable vinyl quinone mono- and diimide substrates I (R = Ac, Me3SiCH2CH2SO2; X = O, NR) undergo cyclization in toluene with HMPA in the dark to provide protected 6-hydroxy and 6-amino dihydroquinolines II (R = Ac, Me3SiCH2CH2SO2; X = O, NR) in 55-71% yields. Aromatization of I (R = Ac, Me3SiCH2CH2SO2; X = O, NR) provides the corresponding quinolines upon deprotection of the dihydroquinoline nitrogens. The substrates I are prepared from bromophenylenediamines and bromoaminophenols using a Stille coupling to assemble the framework followed by deprotection (if needed) and oxidation to generate the quinone imides. When the quinone monoimides I (R = Ac, Me3SiCH2CH2SO2; X = O) are stirred in toluene with HMPA under ambient light, the hydroxyindoles III (R = Ac, Me3SiCH2CH2SO2) are obtained instead in 59-69% yields. In the experiment, the researchers used many compounds, for example, 4-Amino-3-bromophenol (cas: 74440-80-5Related Products of 74440-80-5).
4-Amino-3-bromophenol (cas: 74440-80-5) belongs to organobromine compounds. Bromo compounds are employed in a variety of metal-catalyzed coupling reactions. They are also ideal candidates for the synthesis of Grignard reagents that have wide-applicability in organic synthesis. One prominent application of synthetic organobromine compounds is the use of polybrominated diphenyl ethers as fire-retardants, and in fact fire-retardant manufacture is currently the major industrial use of the element bromine.Related Products of 74440-80-5
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary