82868-99-3Relevant academic research and scientific papers
Transition Metal-Catalyzed Oxidations, 6. Total Synthesis of Hallachrome and Related 1,2-Anthraquinones
Krohn, Carsten,Khanbabaee, Karamali
, p. 905 - 910 (2007/10/02)
9,10-Anthraquinones 3b-3k are prepared by Diels-Alder reaction of juglone (5a) and 7-methyljuglone (5b) with the dienes 4a and 4b, then reduced to the corresponding 1-anthracenols 2b-2d, 2f and 2i that are immediately oxygenated to the ortho-anthraquinones 1b-1d, 1f and 1i with *py*HMPT.The 1,2-anthraquinones dimerize in solution or upon BBr3 treatment.The naturally occurring 1,2-anthraquinone hallachrome (1a) is prepared by selective protection of the bisphenol 3h as monosilyl ether 3i, oxygenation to the silylated ortho-anthraquinone 1i and fluoride-mediated deprotection to 1a. Key words: Hallachrome; 1,2-anthraquinones; 9,10-anthraquinones; oxygenation; 1-anthracenols; Mimoun complex.
