Process Improvements in the Synthesis of 2,4,5-Trifluorobenzoic Acid. Selective Hydrodefluorination of Tetrafluorophthalimides
摘要:
An improved preparation of the fluoroquinolone antibacterial intermediate 2,4,5-trifluorobenzoic acid is described. A combination of a selective hydrodefluorination and hydrolysis reaction of 3,4,5,6-tetrafluoro-N-methylphthalimide leading to 3,5,6-trifluorophthalic acid was key to the success of the profess. In addition the development of a two-step, one-pot imidization/halogen exchange from tetrachlorophthalic anhydride to 3,4,5,6-tetrafluoro-N-methylphthalimide in sulfolane solvent is detailed.
Corollosporine is an antimicrobial metabolite, which was isolated from the marine fungus Corollospora maritima. Owing to its basic 4-hydroxyphthalic acid anhydride structure, it has become an attractive target for a structure/activity relationship modelling of derived compounds with potential antibiotic activity. In this regard we report on the straightforward synthesis of hetero analogous corollosporines, which were easily prepared by a three-step reaction sequence, taking advantage of a novel multicomponent reaction (AAD-reaction) and a subsequent aromatization/Grignard reaction protocol. Furthermore, the obtained products were tested in several biological assays to evaluate their antimicrobial activity.
Unprecedented selective homogeneous cobalt-catalysed reductive alkoxylation of cyclic imides under mild conditions
作者:Jose R. Cabrero-Antonino、Rosa Adam、Veronica Papa、Mattes Holsten、Kathrin Junge、Matthias Beller
DOI:10.1039/c7sc01175j
日期:——
metal-catalysed reductive C2-alkoxylation of cyclicimides (phthalimides and succinimides) is presented. Crucial for the success is the use of [Co(BF4)2·6H2O/triphos (L1)] combination and no external additives are required. Using the optimal cobalt-system, the hydrogenation of the aromatic ring of the parent phthalimide is avoided and only one of the carbonyl groups is selectively functionalized. The
提出了第一个通用且有效的非贵金属催化的环状酰亚胺(邻苯二甲酰亚胺和琥珀酰亚胺)的还原性C2-烷氧基化反应。成功的关键是使用[Co(BF 4)2 ·6H 2 O / triphos(L1)]的组合,并且不需要外部添加剂。使用最佳的钴系统,避免了母体邻苯二甲酰亚胺的芳环的氢化,并且仅羰基中的一个被选择性地官能化。所得的产物,N-和芳基环取代的3-烷氧基-2,3-二氢-1H-异吲哚-1-酮和N-取代的3-烷氧基-吡咯烷基-2-酮衍生物是在温和的条件下以良好至优异的分离产率制备的。分子内还原偶联也可以在一步法中进行,从而得到三环化合物。本协议为药物和生物学关注的功能化N杂环化合物的直接合成开辟了新的贱金属工艺开发途径。
Selective Ruthenium-Catalyzed Reductive Alkoxylation and Amination of Cyclic Imides
作者:Jose R. Cabrero-Antonino、Iván Sorribes、Kathrin Junge、Matthias Beller
DOI:10.1002/anie.201508575
日期:2016.1.4
is the selective ruthenium‐catalyzed reductive alkoxylation and amination of phthalimides/succinimides. Notably, this novel methodology avoids hydrogenation of the aromatic ring and allows methoxylation of substituted imides with good to excellent selectivity for one of the carbonyl groups. The reported method opens the door to the development of new processes for the selectivesynthesis of various
Electroreductive Coupling of Phthalimides with α,β-Unsaturated Carbonyl Compounds and Subsequent Acid-Catalyzed Rearrangement to 4-Aminonaphthalen-1-ols: Density Functional Theory Study of the Acid-Catalyzed Rearrangement of Ketene Silyl Acetals
作者:Naoki Kise、Tatsuhiro Manto、Toshihiko Sakurai
DOI:10.1021/acs.joc.1c02512
日期:2021.12.17
The electroreductive coupling of phthalimides with α,β-unsaturated carbonylcompounds in the presence of TMSCl and successive treatment of the electrochemically coupled products with TFA gave two types of rearranged products, 3- and 2-substituted 4-aminonaphthalen-1-ols. The substituent (R) on the nitrogen atom of phthalimides determined which type of 4-aminonaphthalen-1-ol was preferentially formed
在 TMSCl 存在下,邻苯二甲酰亚胺与 α,β-不饱和羰基化合物的电还原偶联,以及用 TFA 对电化学偶联产物的连续处理,得到了两种类型的重排产物,3-和 2-取代的 4-氨基萘-1-醇。邻苯二甲酰亚胺氮原子上的取代基 (R) 决定了优先形成哪种类型的 4-氨基萘-1-醇。体积较大和体积较小的 N 取代基分别选择性地提供 3-和 2-取代的 4-氨基萘-1-醇。通过密度泛函理论计算,通过电还原偶联产生的甲硅烷基乙烯酮缩醛酸催化重排,推测重排产物的选择性取决于甲硅烷基乙烯酮缩醛的酰胺基团的 O 或 N 质子化是否发生得更快。
Process for producing tetrafluorophthalic acid
申请人:SDS Biotech K.K.
公开号:US04769493A1
公开(公告)日:1988-09-06
A process for producing tetrafluorophthalic acid is disclosed, which comprises the steps of: (a) reacting an alkali metal fluoride and at least one imide compound represented by formula (I) or (II) ##STR1## wherein X.sup.1, X.sup.2, X.sup.3, and X.sup.4, which may be the same or different, each represents a chloride atom or a bromine atom, R.sup.1 represents a monovalent organic group, and R.sup.2 represents a divalent organic group, to provide an N-substituted tetrafluorophthalimide; and (b) hydrolyzing the tetrafluorophthalimide in the presence of an acid.