10.1071/CH16710
The study reports on the successful synthesis and characterization of two 28-membered, 2,2'-bipyridine-containing macrocycles in high yield. The first macrocycle was formed through a Williamson ether synthesis, and upon reduction with sodium borohydride, the second macrocycle was produced quantitatively. These macrocycles, which contain a 2,2'-bipyridine unit, are potentially useful components for creating a variety of interlocked architectures, including catenanes, rotaxanes, and molecular machines. The research builds upon previous work by Sauvage, Stoddart, and Feringa, who were awarded the 2016 Nobel Prize in Chemistry for their contributions to the design and synthesis of molecular machines, and it aims to improve upon the yield-limiting macrocyclisation reactions that have historically been a challenge in the field. The study also discusses the use of high-yielding synthetic strategies and the potential for future investigations into the metal-complexation properties of these ligands and their application in forming interlocked structures.
10.1080/10587250307066
The research presents the synthesis and characterization of a new mesogenic homologous series of Schiff base cinnamates that incorporate a naphthalene moiety. The study aimed to understand the impact of the ethylene linking group (cinnamoyl linkage) and the naphthalene moiety on the mesomorphic properties of these molecules. The reactants used in the synthesis included 4-(40-n-alkoxy cinnamoyloxy) benzaldehydes, 2-amino naphthalene, malonic acid, n-alkyl halide, K2CO3, p-hydroxy benzaldehyde, and solvents like ethanol, which were dried prior to use. The synthesized compounds were characterized using elemental analysis and various spectroscopic techniques, including infrared (IR), ultraviolet (UV), and proton nuclear magnetic resonance (1H NMR) spectroscopy. The study found that all synthesized compounds exhibited mesomorphism, and the mesophase properties were compared with other structurally related series. The results indicated that the presence of the naphthalene moiety and the cinnamoyl linkage influenced the mesophase transition temperatures and the overall thermal stability of the mesophases.
10.1016/j.tetlet.2011.07.035
The research presents a stereoselective synthesis of the naturally occurring pyrrolidine alkaloid, (+)-radicamine B, which possesses significant biological properties. The synthesis involves 13 steps, starting from commercially available p-hydroxybenzaldehyde, with an overall yield of 9.75%. Key reactions include Sharpless asymmetric epoxidation and Horner–Wadsworth–Emmons (HWE) olefination. Reactants used throughout the synthesis include p-hydroxybenzaldehyde, tosyl chloride, (+)-DET, NaN3, PPh3, Boc anhydride, benzaldehyde dimethylacetal, DIBAL-H, IBX, (OEt)2PO(CH2COOEt), and (+)-DIPT, among others. Analytical techniques employed to characterize the intermediates and final product included 1H NMR, 13C NMR, Mass spectrometry, and IR spectroscopy, with enantioselectivity determined by chiral HPLC. The study also discusses the biological significance of radicamine B and the challenges in its asymmetric synthesis, highlighting the efficiency and linearity of their developed synthetic protocol.
10.1080/00397911003707204
The research focuses on the first asymmetric total synthesis of the anti-inflammatory active phenylpropenoid, (R,E)-1-[4-(3-hydroxyprop-1-enyl)phenoxyl]-3-methylbutane-2,3-diol (1), which was isolated from the stem wood of Zanthoxylum integrifoliolum. The purpose of the study was to develop a simple, short, and efficient method for synthesizing this compound using commercially available 4-hydroxy benzaldehyde (2) as the starting material. The key step in the synthesis process involved the Sharpless asymmetric dihydroxylation of olefin (3), which led to the formation of diol aldehyde (4) with high enantioselectivity (95.8% ee). Further reactions, including Wittig olefination and selective reduction, were performed to obtain the target molecule.
Xi
Xi:Irritant;
