2610-95-9Relevant academic research and scientific papers
Aromatic ring synthesis by 1,3-Michael-Claisen annulation: Application to a Trolox analogue and to Precocene II
Solladie,Boeffel,Maignan
, p. 2065 - 2074 (1996)
A Trolox analogue, 3,4-dihydro-2-ethoxycarbonyl-6-methoxy-7-hydroxybenzopyran and Precocene II, were prepared from substituted α-methylene-δ-valerolactone and 1,1-bis-(methylthio)-2-propanone or butanone, via a 1,3-Michael-Claisen annulation.
Cooperative Polar/Steric Strategy in Achieving Site-Selective Photocatalyzed C(sp3)?H Functionalization
Yamada, Keiichi,Fukuyama, Takahide,Fujii, Saki,Ravelli, Davide,Fagnoni, Maurizio,Ryu, Ilhyong
, p. 8615 - 8618 (2017)
Synergistic control over the SH2 transition states of hydrogen abstraction exploiting polar and steric effects provides a promising cooperative strategy for site-selective C(sp3)?H functionalization using decatungstate anion photocatalysis. By using this photocatalytic approach, the C?H bonds of substituted lactones and cyclic ketones were functionalized selectively. In the remarkable case of 2-isoamyl 4-tert-butyl cyclohexanone (1 t) bearing five methyl, five methylene, and three methine C?H bonds, one methine C?H bond in the isoamyl tether was selectively functionalized.
Synthesis of the ester side chains of homoharringtonine and harringtonine using lactones as building blocks
Dang, Fang-Fang,Wang, Cui-Cui,Han, Feng,Zhang, Zhi-Wei
supporting information, p. 317 - 323 (2020/10/14)
The efficient synthesis of the ester side chains of homoharringtonine and harringtonine using lactones as building blocks has been developed. The synthesis used classic reactions from readily available starting materials. Reactions of the lactone bearing
Green Oxidation of Ketones to Lactones with Oxone in Water
Bertolini, Valentina,Appiani, Rebecca,Pallavicini, Marco,Bolchi, Cristiano
, p. 15712 - 15716 (2021/11/01)
Cyclic ketones were quickly and quantitatively converted to 5-, 6-, and 7-membered lactones, very important synthons, by treatment with Oxone, a cheap, stable, and nonpollutant oxidizing reagent, in 1 M NaH2PO4/Na2HPO4 water solution (pH 7). Under such simple and green conditions, no hydroxyacid was formed, thus making the adoption of more complex and non-eco-friendly procedures previously developed to avoid lactone hydrolysis unnecessary. With some changes, the method was successfully applied also to water-insoluble ketones such as adamantanone, acetophenone, 2-indanone, and the challenging cycloheptanone.
Calcium(II)- And Triflimide-Catalyzed Intramolecular Hydroacyloxylation of Unactivated Alkenes in Hexafluoroisopropanol
Qi, Chenxiao,Yang, Shengwen,Gandon, Vincent,Leb?uf, David
supporting information, p. 7405 - 7409 (2019/10/02)
We report an efficient intramolecular hydroacyloxylation of unactivated alkenes, offering a streamlined access to relevant γ-lactones, which features the utilization of either a calcium(II) salt or triflimide as a catalyst in hexafluoroisopropanol. This method could be applied to the synthesis of natural products and the late-stage functionalization of natural and bioactive molecules. Additionally, DFT computations were used to elucidate the twist of reactivity observed between the hydroamidation and hydroacyloxylation of unactivated alkenes regarding the formation of 5- and 6-membered rings.
C-H oxygenation at tertiary carbon centers using iodine oxidant
Kiyokawa, Kensuke,Ito, Ryo,Takemoto, Kenta,Minakata, Satoshi
supporting information, p. 7609 - 7612 (2018/07/15)
An oxidation system in which iodic acid (HIO3) is used as an oxidant in the presence of N-hydroxyphthalimide (NHPI) permitted the selective hydroxylation of tertiary C-H bonds and the lactonization of carboxylic acids containing a tertiary carbon center. These reactions are operationally simple and proceed under metal-free conditions using commercially available reagents, thus offering an ideal tool for the efficient oxidation of C-H bonds at tertiary carbon centers.
Formation of δ-Lactones with anti-Baeyer–Villiger Regiochemistry: Investigations into the Mechanism of the Cerium-Catalyzed Aerobic Coupling of β-Oxoesters with Enol Acetates
Geibel, Irina,Dierks, Anna,Müller, Thomas,Christoffers, Jens
, p. 7245 - 7254 (2017/05/31)
The cerium-catalyzed, aerobic coupling of β-oxoesters with enol acetates and dioxygen yields δ-lactones with a 1,4-diketone moiety. In contrast to the Baeyer–Villiger oxidation (BVO), where the higher substituted residue migrates; in the case of this oxid
Efficient and Selective Cu/Nitroxyl-Catalyzed Methods for Aerobic Oxidative Lactonization of Diols
Xie, Xiaomin,Stahl, Shannon S.
supporting information, p. 3767 - 3770 (2015/04/14)
Cu/nitroxyl catalysts have been identified that promote highly efficient and selective aerobic oxidative lactonization of diols under mild reaction conditions using ambient air as the oxidant. The chemo- and regioselectivity of the reaction may be tuned by changing the identity of the nitroxyl cocatalyst. A Cu/ABNO catalyst system (ABNO = 9-azabicyclo[3.3.1]nonan-N-oxyl) shows excellent reactivity with symmetrical diols and hindered unsymmetrical diols, whereas a Cu/TEMPO catalyst system (TEMPO = 2,2,6,6-tetramethyl-1-piperidinyl-N-oxyl) displays excellent chemo- and regioselectivity for the oxidation of less hindered unsymmetrical diols. These catalyst systems are compatible with all classes of alcohols (benzylic, allylic, aliphatic), mediate efficient lactonization of 1,4-, 1,5-, and some 1,6-diols, and tolerate diverse functional groups, including alkenes, heterocycles, and other heteroatom-containing groups.
Highly practical copper(I)/TEMPO catalyst system for chemoselective aerobic oxidation of primary alcohols
Hoover, Jessica M.,Stahl, Shannon S.
supporting information; experimental part, p. 16901 - 16910 (2011/12/04)
Aerobic oxidation reactions have been the focus of considerable attention, but their use in mainstream organic chemistry has been constrained by limitations in their synthetic scope and by practical factors, such as the use of pure O2 as the oxidant or complex catalyst synthesis. Here, we report a new (bpy)CuI/TEMPO catalyst system that enables efficient and selective aerobic oxidation of a broad range of primary alcohols, including allylic, benzylic, and aliphatic derivatives, to the corresponding aldehydes using readily available reagents, at room temperature with ambient air as the oxidant. The catalyst system is compatible with a wide range of functional groups and the high selectivity for 1° alcohols enables selective oxidation of diols that lack protecting groups.
Structural and stereochemical requirements of the spiroketal group of hippuristanol for antiproliferative activity
Li, Wei,Dang, Yongjun,Liu, Jun O.,Yu, Biao
scheme or table, p. 3112 - 3115 (2010/09/08)
Hippuristanol is a natural product that has recently been shown to inhibit eukaryotic translation initiation and tumor cell proliferation. To investigate the structure and activity relationship of hippuristanol, we synthesized a series of analogs by expan
