Ondogyne,Roussel,France,1970
(A) Preparation of p-Hydroxy-p'-Methoxybenzhydrylidenecyclohexane: To a
Grignard solution prepared from 110 g of magnesium (4.5 mols) and 840 g of
p-bromoanisole (4.5 mols) in one liter of anhydrous ether, there was added
dropwise with vigorous agitation 307 g of p-hydroxyphenyl cyclohexyl ketone
(1.5 mols) dissolved in one liter of anhydrous ether. Upon completion of the
addition the reaction mixture was refluxed for 2.5 hours with agitation, and
was then cooled. Thereupon 15 mols of ammonium chloride dissolved in 3
liters of water were added. The ethereal layer was separated, washed with
water, dried over anhydrous sodium sulfate and distilled. Yield: 370 g. BP
180° to 190°C at 0.1 mm. The substance was recrystallized from a mixture of
carbon tetrachloride and petroleum ether. MP 145° to 146°C.
(B)Preparation of p,p'-Dihydroxybenzhydrylidenecyclohexane: A mixture of
118 g of p-hydroxy-p'-methoxybenzhydrylidenecyclohexane (0.4 mol), 120 g
of potassium hydroxide pellets and 500 ml of triethylene glycol was stirred 4
hours at 220°C. When the reaction mixture was poured into water the
substance crystallized, and the crystals were filtered off and washed with water. The substance was then recrystallized from a mixture of ethanol and
petroleum ether. Yield: 104 g. MP 235° to 236°C.
(C) Preparation of p,p'-Diacetoxybenzhydrylidenecyclohexane: 56 g of p,p'-
dihydroxybenzhydrylidenecyclohexane (0.2 mol) was mixed with 250 ml of
acetic anhydride and 500 ml of pyridine. The mixture was refluxed for 2 hours
and was then poured into water, the substance crystallizing out. The crystals
were filtered off and washed with water. Finally the substance was
recrystallized from ethanol. Yield: 62 g. MP 135° to 136°C.
