10516-71-9Relevant articles and documents
Grob-Type Fragmentation Releases Paracyclophane Ring Strain in a Late-Stage Precursor of Haouamine A
Cao, Liming,Wang, Chenbo,Wipf, Peter
, p. 1538 - 1541 (2019)
A ketene [2 + 2]-addition, an intramolecular aldol reaction, a Suzuki-Miyaura coupling, and a chemoselective lactam reduction were used to prepare a late-stage precursor of haouamine A. Exposure to acid led to a Grob-type fragmentation of the strained 3-aza[7]paracyclophane ring, followed by a tandem Pictet-Spengler reaction of the intermediate iminium ion and conversion to a novel 1,4a-propanocyclopenta[b]pyridine. This cascade reaction might also be relevant for the mechanism of action of the natural product.
Samarium diiodide reduction of cinnamic acids
Lin, Tzuen-Yeuan,Fuh, Ming-Ren,Tsau, Chi-Yu
, p. 917 - 921 (2004)
The method for measuring SmI2 reduction rates is expanded to a wider range of organic compounds by using not only GC or GC/MS, but also HPLC as the detecting tool. The reduced substrates are not only confined to water insoluble compounds or low boiling compounds only. Water soluble cinnamic acid derivatives of high boiling points are chosen for this application. The absolute rate constants of SmI2 reduction of cinnamic acid in the presence of hexamethyl phosphoramide or t-butanol is considered as a suitable proton source in this reaction. The rates are dependent on substrates and additives as: Rate · [t-BuOH][Cinnamic acid] and Rate · [HMPA][Cinnamic acid] The reduction rates of α-methylcinnamic acid, 2-methylcinnamic acid, 4-methylcinnamic acid, 2-methoxycinnamic acid, 3-methoxycinnamic acid, 4-methoxycinnamic acid, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid, 4-hydroxycinnamic acid, 2-chlorocinnamic acid, 3-chlorocinnamic acid, 4-chlorocinnamic acid were carefully measured to study the substituent effect.
Siloxyl ether functionalized resins for chemoselective enrichment of carboxylic acids
Trader, Darci J.,Carlson, Erin E.
, p. 5652 - 5655 (2011)
Although the carboxylic acid moiety is prevalent in many biologically produced molecules, including natural products and proteins, methods to chemoselectively target this functional group have remained elusive. Generally, strategies that utilize carboxylate nucleophilicity also promote reactions with other nucleophiles such as amines and hydroxyls. A reagent was sought to facilitate the selective isolation of carboxylic acid containing compounds from complex mixtures. Here, the development of siloxyl ether functionalized solid supports is described.
Xylochemistry - Making Natural Products Entirely from Wood
Stubba, Daniel,Lahm, Günther,Geffe, Mario,Runyon, Jason W.,Arduengo, Anthony J.,Opatz, Till
, p. 14187 - 14189 (2015)
The first total synthesis of the dimeric berberine alkaloid ilicifoline (ilicifoline B) is reported. Its carbon skeleton is constructed from ferulic acid, veratrole, and methanol. The synthesis reported herein employs starting materials solely derived from wood. The natural product is thus constructed entirely from renewable resources. The same strategy is applied to a formal total synthesis of morphinan alkaloids. The use of wood-derived building blocks (xylochemicals) instead of the conventional petrochemicals represents a sustainable alternative to classical synthetic approaches.
Aldehyde as a Traceless Directing Group for Regioselective C-H Alkylation Catalyzed by Rhodium(III) in Air
Chen, Si-Qi,Fan, Juan,Li, Chao-Jun,Li, Xin-Ran,Liu, Zhong-Wen,Shi, Xian-Ying
supporting information, p. 1259 - 1264 (2020/03/13)
The aromatic aldehyde as a traceless directing group for the regionselective C-H alkylation catalyzed by rhodium(III) under aerobic atmospheric conditions has been developed. The process involves an aldehyde assisted direct addition of C-H bond to unsaturated electrophiles of acrylates or acrylic acids, and the subsequent decarbonylation. A trace amount of water is found to favor the reaction.
Synthetic and Mechanistic Studies on 2,3-Dihydrobenzo[ b ][1,4]-oxaselenines Formation from Selenocyanates
Bonesi, Sergio M.,Cattaneo, Mauricio,Chao, María N.,Rodriguez, Juan B.,Sanchez Gonzalez, Jonathan,Szajnman, Sergio H.
, p. 1643 - 1658 (2020/05/25)
An expedient preparation of selenium-containing hetero-cycles via an m -chloroperbenzoic acid-mediated seleno-annulation starting from selenocyanate derivatives is described. In spite of its significance, this cyclization reaction is virtually understudied not only from the point of view of its scope, but also from the mechanistic aspects associated to this remarkable transformation. In this sense, several selenocyanate and thiocyanate derivatives bearing an aromatic ring were evaluated as substrates under different reaction conditions of this interesting cyclization yielding important insights on its scope as well as relevant information on the reaction mechanism.