Methylhydroquinone, phenylhydroquinone, 그리고 tert-butylhydroquinone들과 같은 수산기로 치환된 벤젠류들을 이소부틸렌이나 티-부탄올과 같은 알킬화제로 산촉매하에서 목적하는 2.5-substituted hydroquinones를 생산하기 위한 제반조건들을 연구하였다. 양이온으로 교환된 수지촉매로서 Amberlyst-15 또는 70% 황산을 촉매로 사용하여 회분식 반응기에서 알킬화 반응을 하였는데, 용매로서 사이클로헥산과 2-헵타논(혹은 에틸 아세테이트)이 훌륭한 것으로 알 수 있었다. 액체산 촉매인 70% 황산보다 고체산 촉매인 Amberlyst-15를 사용할 경우 목적하는 2,5-substituted hydroquinones의 선택성이 상대적으로 더 좋음을 볼 수 있었다. 이러한 결과는 고체산 촉매인 Amberlyst-15에서 활성점인 고정된 양이온들에 의한 입체 장애(steric hindrance)로 인하여 원하는 2,5-substi-tuted hydroquinones의 선택도가 더 높음을 알 수 있었다. 다른 관점으로 선택도의 변화를 볼 때 다영한 hydroqui-none류에 치환된 기(group)에 의해 역시 영향을 받는데, tert-butyl, phenyl 그리고 methylhydroquinones의 순으로 원하는 2,5-substituted hydroquinones의 선택도가 감소함을 알 수 있었다. 한편 반응후 생성물로부터 주생성물인 2,5-substituted hydroquinones를 얻기 위하여 추출 및 결정화방법을 사용하여 성공적으로 분리할 수 있었다.

The alkylation of hydroxy-benzenes, such as methylhydroquinone, phenylhydroquinone, and tert-butylhydroquinone, was studied utilizing isobutylene or tert-butanol as the alkylating agent to obtain 2,5-substi-tuted hydroquinones. The alkylation was carried out in the presence of acid catalysts such as Amberlyst-15 or 70% sulfuric acid in a batch reactor. As reactiion solvent, a mixture of cyclohexane and 2-heptanone or ethyl acetate was found to be a good solvent system. The cation exchange resin catalyst Amberlyst-15 offered better selectivity to 2.5-substituted hydroquinones than 70% sulfuric acid. a steric hindrance imposed of fixed protons in solid acid catalyst such as Ambr\erlyst-15 caused higher selectivity toward less-hindered position. It was also found that the selectivity was affected by groups substituted on hydroquinones; the selectivity of 2,5-substituted hydroquinones was in the descending order of tert-butyl, phenyl, and methyl-hydroquinones. The separation of 2.5-substituted hydroquinones from the reaction mixture was successfully accomplished by utilizing extraction and crystallization.

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