... Chem. 1886, 51, 419. (4) For an excellent review on the chemistry of orthoquinones see ... Page 5. J. Org. Chem. 1987,52,4489-4494 4489 resultant solution was extracted with 10% NaOH (2 X 100 mL). The organic layer was dried with MgSOl and the solvent removed. ...