
TY  - JOUR
A1  - Cooke, RG 
A1  - Somers, TC 
T1  - Dunnione and related naphthoquinones. III. Rearrangement of hydroxynaphthoquinones to indenone carboxylic acids. <I>allo</I>dunnione
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1950
VL  - 3
IS  - 3
SP  - 487
EP  - 496
KW  - 
UR  - https://doi.org/10.1071/CH9500487 
N2  - Certain tert.-alkylhydroxynaphthoquinones are found to isomerize rapidly in hot aqueous alkali, and the reaction is correlated with the rearrangement of dunnione to allodunnione. The change also occurs, relatively slowly, with 2-hydroxy-3-isopropyl- 1,4-naphthoquinone. An alternative synthesis shows that the product in this case is 2-iaopropyl-indenone-3-carboxylic acid. The ethyl ester of this acid shows an absorption spectrum very similar to that of allodunnione.   Alkaline rearrangement of 2-hydroxy-3-(1,1-dimethylallyl)-1,4-naphthoquinone evidently gives the corresponding dimethylallylindenonecarboxylic acid. Treatment of the latter with concentrated sulphuric acid forms allodunnione, and a new isomer which apparently results from a retropinacolinic rearrangement. All these observations support the structure originally proposed for allodunnione. 
ER  -

