ZnAlMCM-41: a very ecofriendly and reusable solid acid catalyst for the highly selective synthesis of 1,3-dioxanes by the Prins cyclization of olefins
作者:Manickam Selvaraj、Mohammed A. Assiri、Hari Singh、Jimmy Nelson Appaturi、Ch. Subrahmanyam、Chang-Sik Ha
DOI:10.1039/d0dt04158k
日期:——
formaldehyde (FCHO)) under different reaction conditions to obtain 1,3-dioxanes, which are widely used as solvents or intermediates in organic synthesis. Based on the nature of catalysts used under different reaction conditions, a reasonable plausible reaction mechanism for the Prins cyclization of SE with PFCHO is proposed. Notably, it can be seen from the catalytic results of all catalysts that the W-ZnAlMCM-41(75)
使用液相非均相催化方法,用介孔ZnAlMCM-41催化剂对苯乙烯(SE)与低聚甲醛(PFCHO)进行Prins环化反应,以合成4-苯基-1,3-二恶烷(4-PDO)。为了进行比较研究,还对不同的纳米多孔催化剂进行了Prins环化反应,例如介孔固体酸催化剂AlMCM-41(21)和ZnMCM-41(21),以及微孔催化剂USY,Hβ,HZSM-5和H-丝光沸石。可回收的介孔ZnAlMCM-41催化剂在该反应中被重复使用以评估其催化稳定性。由于ZnAlMCM-41(75)具有比其他固体酸催化剂更高的催化活性,因此使用有效的化学处理方法制备了洗涤后的ZnAlMCM-41(75)/ W-ZnAlMCM-41(75),并使用了各种反应参数来寻找4-PDO高选择性合成的最佳参数。W-ZnAlMCM-41(75)还用于在不同反应条件下用PFCHO和福尔马林(FN,37%甲醛水溶液(FCHO))对烯烃进行Prins环化反应,得到了1