88007-98-1Relevant academic research and scientific papers
Transition metal-free cyclobutene rearrangement in fused naphthalen-1-ones: Controlled access to functionalized quinones
Herrera, Fernando,Luna, Amparo,Fernández, Israel,Almendros, Pedro
supporting information, p. 1290 - 1293 (2020/02/04)
The controlled synthesis of 1,4-naphthoquinones and tetraphene-7,12-diones, which bear the ABCD-ring of landomycins, has been accomplished directly through oxidative rearrangement of common stable precursors, namely, previously non-isolable cyclobuta[a]naphthalen-4(2H)-ones.
Pyridinium Ylides in Syntheses of Naphthopyrandiones and in Regioselective Syntheses of Acylated Anthraquinones Related to Fungal and Bacterial Metabolites
Aldersley, Michael F.,Chishti, Shuhid H.,Dean, Francis M.,Douglas, Mark E.,Ennis, David S.
, p. 2163 - 2174 (2007/10/02)
Improvements have been made in the use of acylated pyridinium ylides for the transformation of 2-methyl-1,4-naphthoquinone into derivatives (15) and (16) of naphthopyran-5,10-dione, containing furan and thiophene groups.The substitution and cyclisation steps can be combined effectively by using 2-phenoxymethyl- instead of 2-methyl-naphthoquinone.The use of better leaving groups than phenoxy (especially 4-nitrophenoxy) allows the quinone to react with two proportions of ylide and leads regiospecifically to 1-aroyl-2-arylanthracene-9,10-diones such as (20a).If the leaving group is nuclear bromine as in 2-bromo-3-methyl-1,4-naphthoquinone, another reaction with 2 mol equiv. of ylide leads to complex red intermediates of type (31) which in contact with alumina are quantitatively converted into the regioisomeric 2-aroyl-3-arylanthracene-9,10-diones such as (22a).The structures have been determined by standard methods but special features of the NMR spectra are reported including a case of extreme line broadening by traces of iron.Mechanisms are suggested for the diverse reactions between the quinones and the ylides.
Alkylation of Quinones by Carbanions: Use of Pyridinium Ylides to insert Phenacyl, Acetonyl and Related Groups
Aldersley, Michael F.,Dean, Francis M.,Nayyir-Mazhir, Rassoul
, p. 1753 - 1757 (2007/10/02)
Reports that carbanions C- add to quinones Q in the ratios 1:1 and 2:1 are confirmed; even if an excess of quinone is present, cage or bridge products are formed only if the carbanion is itself quinonoid.Pyridinium salts C5H5N+CH2COR
