liquid leads to a significant improvement of catalyst selectivity. Many organic reactions, including Prins cyclization, cycloaddition of epoxide to aldehyde, and dehydrative etherification of secondary benzyl alcohols, proceed well in formalin or pure water. In particular, tandem dehydration/Prins cyclization reactions of tertiary and secondaryalcohols with formaldehyde were developed for the first time
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。
[DE] VERFAHREN ZUR HERSTELLUNG VON DIHYDROZIMTALDEHYDEN<br/>[EN] PROCESS FOR PREPARING DIHYDROCINNAMIC ALDEHYDES<br/>[FR] PROCEDE DE PREPARATION D'ALDEHYDES DIHYDROCINNAMIQUES
申请人:HENKEL KOMMANDITGESELLSCHAFT AUF AKTIEN
公开号:WO1995021808A1
公开(公告)日:1995-08-17
(DE) Durch katalytische Dehydrierung von Dihydrozimtalkoholen bei mäßigen Temperaturen sind die entsprechenden Dihydrozimtaldehyde in hohen Ausbeuten bei gleichzeitig guter geruchlicher Qualität zugänglich.(EN) Dihydrocinnamic aldehydes may be prepared in high yields and with a good odour by catalytic dehydrogenation of dihydrocinnamic alcohols at moderate temperatures.(FR) On peut préparer des aldéhydes dihydrocinnamiques en grandes quantités et ayant une bonne odeur par déshydrogénation catalytique d'alcools dihydrocinnamiques à des températures modérées.
通过一级催化脱水,在温和温度下可以实现从一级羟烷基醇到烯醛的高效转化。
Prins Cyclization of Styrenes or Acetophenone Catalyzed by DBSA in Water
作者:Juan Zhang、Lin Hua、Feifei Li、Xuefen Wu、Shengzhi Tian、Jing Yang
DOI:10.1080/00397911.2010.538891
日期:2012.4.15
Dodecylbenzenesulfonic acid (DBSA) was proved to be an efficient catalyst for Prins cyclization of styrenes and formaldehyde or acetaldehyde in water. A tandem dehydration/Prins cyclization reaction using a tertiary alcohol and formaldehyde as substrates proceeded very well by using DBSA as catalyst. Acetophenone, which is less reactive compared with styrene, can also react with formaldehyde when catalyzed by DBSA in water to afford 1,3-dioxan-5-ylphenylmethanone in good yield.
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)