
TY  - JOUR
A1  - Cameron, DW 
A1  - Feutrill, GI 
A1  - Mckay, PG 
T1  - Regiospecific synthesis of quinizarin and naphthazarin derivatives by cycloaddition
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1982
VL  - 35
IS  - 10
SP  - 2095
EP  - 2109
KW  - 
UR  - https://doi.org/10.1071/CH9822095 
N2  - The diene (E)-1,1,4-trimethoxybuta-1,3-diene underwent regiospecific cycloaddition to derivatives of 2(3)-chloro-1,4-naphthoquinone. The resulting adducts were aromatized to give 1,4-dioxygenated anthraquinones. The latter were obtained as derivatives of quinizarin dimethyl ether or of quinizarin monomethyl ether depending on the conditions of aromatization. Cycloaddition of the diene to non-halogenated naphthoquinones proceeded similarly, orientation being controlled by substituents in the benzenoid ring. Analogous reaction of the diene with benzoquinones gave 5,8-dioxygenated naphthoquinones (naphthazarins), generally in limited yield. The procedure has been applied to synthesis of the mould metabolites helminthosporin and cynodontin. 
ER  -

