82247-15-2

Upstream product

• 84064-72-2 threo-1-(3,4-Dimethoxyphenyl)-1-(9,10-dihydroxyanthracen-10-yl)-2-(2-methoxyphenoxy)propane 
• 82247-06-1 10-[(1S,2S)-1-(3,4-Dimethoxy-phenyl)-2-(2-methoxy-phenoxy)-propyl]-10-hydroxy-10H-anthracen-9-one 
• 28871-54-7 9-anthrol trimethylsilyl ether 
• 86956-05-0 1-bromo-1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)propane 

Relevant academic research and scientific papers

Adducts of Anthrahydroquinone and Anthranol with Lignin Model Quinone Methides. 2. Dehydration Derivatives. Proof of Threo Configuration

NMR studies of novel dehydration derivatives of anthrahydroquinone (AHQ)-lignin and anthranol-lignin model quinone methide adducts have confirmed the sole diastereomeric form of the adducts as "threo".Upon dehydration of the AHQ adduct 1-(3,4-dimethoxyphenyl)-1-(10-hydroxy-9-oxoanthracen-10-yl)-2-(2-methoxyphenoxy)propane with polyphosphoric acid, the spiro compound 3'-(3,4-dimethoxyphenyl)-2',3'-dihydro-8'-methoxy-2'-methylspirobenzopyran>-10-one (3b) was obtained.Reduction of the anthranol adduct 1-(3-methoxy-4-hydroxyphenyl)-1-(9-oxoanthracen-10-yl)-2-(2-methoxyphenoxy)pro pane with LiAlH4, followed by dehydration with BF3*Et2O gave the bicyclic compound 10,11-dihydro-2,3-dimethoxy-11--5,10-o-benzeno-5H-dibenzocycloheptene (7d).Coupling constants of the aliphatic protons in 3b and 7d are consistent only with the threo form.Therefore, by analogy, all other reported AHQ and anthranol adducts with asymmetry of Cα and Cβ are assigned the threo configuration.

Adducts of Anthrahydroquinone and Anthranol with Lignin Model Quinone Methides. 3. Independent Synthesis of Threo and Erythro Isomers

A key intermediate responsible for anthrahydroquinone- (AHQ-) catalyzed delignification of wood under alkaline conditions is an adduct between AHQ and a quinone methide (QM) of a phenylpropanoid lignin subunit represented by models such as 1-(3-methoxy-4-hydroxyphenyl)-2-(2-methoxyphenoxy)propane-1,3-diol.Unlike adduct formation via QMs, which give only threo products with AHQ or anthranol (9-hydroxyanthracene), both isomers were successfully prepared by alkylating 9,10-bis(trimethylsiloxy)anthracene or 9-(trimethylsiloxy)anthracene with α-bromo derivatives of ligninmodels in the presence of the Lewis acid zinc bromide.It is demonstrated by 1H NMR spectroscopy that the solution conformations of erythro adducts are marcedly different from those of the threo adducts and that the conformations vary with substitution and changes in solvent.Also, the erythro isomers are relatively unstable and readily isomerize under the alkylation conditions.