The introduction of a hydroxyl function into phenol to give hydroquinone and catechol can be achieved in high yields by the reaction of hydrogen peroxide with alkenylphenols. These alkenylphenols are obtained by thermolysis of bisphenol A, alkylation of phenol with cyclopentadiene followed by isomerization, and alkylation of phenol with mesityl oxide followed by thermolysis to give 4-isopropenylphenol, 2-and 4-(cyclopenten-l-yl)phenol, and 2,2,4-trimethyl-l,2-chromene, respectively.

No abstract

cyanogen in 35 ml of ethyl acetate was prepared in the usual manner in the dark at 0°. To this cold solution was added 7.2 mmol of I in 20 ml of ethyl acetate over at 15-min period. At this point tic indicated that no thiol remained. The appropriate thioether (7.2 mmol) was dissolved in 25 ml of ethyl acetate and added in one portion to the reaction mixture. The solution was stirred in the dark for 2 hr at 0°, allowed to warm to room temperature, and stirred for an additional period of time (3-33 hr depending on the reaction progress as demonstrated by tic). After reaction was complete the solution was diluted to 200 ml with ethyl acetate and washed with 5% sodium bicarbonate solution, water, and saturated brine. The organic extract was dried and evaporated in vacuo, and the residue was triturated with hexane to remove the trityl thiocyanate. The resulting powder was purified by recrystallization or chromatography followed by recrystallization. The reported yields (Table I) are based on the amount of purified product.B. Acidic Solvents.-To a cold, stirred solution containing 9 mmol of thio cyanogen in 35 ml of ethyl acetate was added 7.2 mmol of I in 20 ml of trifluoroacetic acid (TEA). After 10 min,

The known polymerization of 4,4′‐difluorobenzophenone (DFB) with the dianion of hydroquinone to poly(phenylene ether ether ketone) (PEEK) and polymerization of either DFB with the dianion of 4,4′‐dihydroxybenzophenone or self polycondensation of the anion of 4‐hydroxy‐4′‐fluoro‐benzophenone to poly(phenylene ether ketone) (PEK) were studied in N‐cyclohexyl‐2‐pyrrolidone (CHP), which is a high‐boiling aprotic polar solvent. The formation of high‐molecular weight PEEK and PEK in this solvent was very efficient. The reactivity in CHP can be ascribed to effective solvation of metal ions rendering the anion very reactive toward nucleophilic substitution. The polymerization was extended to 4,4′‐bis(4‐fluorobenzoyl)diphenyl ether and 1,4‐bis[4‐(4‐fluorobenzoyl)phenoxy]benzene to give a high molecular weight polymer with PEK and PEEK repeating units and PEEK respectively. The polymerization of DFB with purified anhydrous sodium sulfide in CHP gave rapidly a high molecular weight poly(phenylene ketone sulfide) (PKS). In contrast, diphenyl sulfone (DPS) was not very effective in obtaining such a high molecular weight PKS even with prolonged heating, which suggests the uniqueness of CHP in promoting a high degree of polymerization.

Alkyl and aryl isothiocyanates react with oxalyl chloride (1) on both double bonds of the heterocumulene to yield 3-alkylor 3-aryl-2,2-dichlorothiazolidine-4,5-diones 2. The two chlorines in these novel orthocarbonic acid derivatives are readily exchanged by alkoxy groups to yield 2,2-dialkoxythiazolidine-4,5-diones 3; hydrolysis of 2a (R = CH3) gave 3-methylthiazolidine-2,4,5-trione. 3-Substituted 5,5-dichlorooxazolidine-2,4-diones 8 and 5-chloro-5-alkoxyoxazolidine-2,4-diones 13 are obtained on reacting alkyl, aryl, and benzyl isocyanates with 1 and alkyloxalyl chloride, respectively. Structure assignment to these novel cycloadducts is based on IR, XH NMR, and 13C NMR spectroscopic as well as X-ray crystallographic analysis. Formation of 8 and 13 is a stepwise process involving labile acyclic intermediates 7 and 12. The cyclizations to 8 and 13 take place only on the C=N bond