The Prins reaction of styrenes with paraformaldehyde or 1,3,5-trioxane in toluene in the presence of cation-exchanged montmorillonite (Mn+-mont), which worked as a Brønsted acid catalyst, at 80 °C produced 4-aryl-1,3-dioxanes selectively in up to 99% isolated yield with a turnover number of up to 5.9 × 102. Among the examined 21 Mn+-monts, Ce3+- and Fe3+-monts were revealed to be quite effective. Regeneration of the catalyst was confirmed with the Ce3+-mont, which could be effectively recycled at least three times. Many lanthanide metal ion-exchanged montmorillonites (Ln3+-monts) were prepared and characterized by X-ray powder diffraction (XRD) and temperature-programmed desorption of ammonia gas (NH3-TPD) methods.
The Catalytic Asymmetric Intermolecular Prins Reaction
作者:C. David Díaz-Oviedo、Rajat Maji、Benjamin List
DOI:10.1021/jacs.1c10245
日期:2021.12.15
Despite their significant potential, catalytic asymmetric reactions of olefins with formaldehyde are rare and metal-free approaches have not been previously disclosed. Here we describe an enantioselective intermolecular Prins reaction of styrenes and paraformaldehyde to form 1,3-dioxanes, using confined imino-imidodiphosphate (iIDP) Brønsted acid catalysts. Isotope labeling experiments and computations
尽管它们具有巨大的潜力,但烯烃与甲醛的催化不对称反应是罕见的,并且以前没有公开过不含金属的方法。在这里,我们描述了苯乙烯和多聚甲醛的对映选择性分子间 Prins 反应以形成 1,3-二恶烷,使用受限的亚氨基-亚氨基二磷酸 ( i IDP) 布朗斯台德酸催化剂。同位素标记实验和计算表明酸活化甲醛低聚物向烯烃中的协同、高度异步添加。对映体富集的 1,3-二恶烷可以转化为相应的光学活性 1,3-二醇,它们是有价值的合成构件。
Selective Prins Reaction of Styrenes and Formaldehyde Catalyzed by 2,6-Di-<i>tert</i>-butylphenoxy(difluoro)borane
作者:Thorsten Bach、Johannes Löbel
DOI:10.1055/s-2002-35645
日期:——
The sterically congested Lewis acid 1 was used as a catalyst in the Prins reaction of various styrenes and formaldehyde. 4-Aryl-1,3-dioxanes 5 were selectively formed as the exclusive products of the reaction with styrenes 4a-i and vinylthiophenes 4j-k. The reaction proceeded in most cases with good to excellent yields (55-99%). Styrenes which carried a strongly electron-withdrawing group (CN. CO 2
Facile and Efficient Method for the Prins Reactions of Styrenes and Homoallyl Alcohols to 1,3‐Dioxanes and 4‐Tetrahydropyranols Using Bismuth(III) Triflate
Abstract Bismuth(III) triflate has been found to be an efficient catalyst for the Prins reactions of styrenes and homoallyl alcohols, the reaction proceeds rapidly and affords the corresponding 1,3‐dioxanes and tetrahydropyran‐4‐ol in good yields. Scope and limitations of the styrenes and homoallyl alcohols are reported.
Novel Hydrophobic Brønsted Acidic Ionic-liquids as Efficient and Reusable Catalysts for Organic Reactions in Water
作者:Yanlong Gu、Chikako Ogawa、Shu Kobayashi
DOI:10.1246/cl.2006.1176
日期:2006.10
Novel hydrophobic Brønsted acidic ionic liquids (HBAIL) were prepared and utilized as acid catalysts in organic reactions in water. HBAILs were demonstrated, for the first time, to be effective catalysts for Prins cyclization of styrene derivatives in water with a formaldehyde water solution. Many styrene derivatives could be successfully converted to the corresponding 1,3-dioxanes. Other dehydration reactions also proceeded well using HBAILs in water. After reactions, HBAILs could be easily recovered and reused without significant loss of activity.