97510-97-9Relevant academic research and scientific papers
Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydroboration and Dehydroboration
Bloomer, Brandon,Butcher, Trevor W.,Ciccia, Nicodemo R.,Conk, Richard J.,Hanna, Steven,Hartwig, John F.
, p. 1005 - 1010 (2022/02/10)
We report a dehydroboration process that can be coupled with chain-walking hydroboration to create a one-pot, contra-thermodynamic, short-or long-range isomerization of internal olefins to terminal olefins. This dehydroboration occurs by a sequence comprising activation with a nucleophile, iodination, and base-promoted elimination. The isomerization proceeds at room temperature without the need for a fluoride base, and the substrate scope of this isomerization is expanded over those of previous isomerizations we have reported with silanes.
Cu-Catalyzed Hydroxymethylation of Unactivated Alkyl Iodides with CO To Provide One-Carbon-Extended Alcohols
Zhao, Siling,Mankad, Neal P.
supporting information, p. 5867 - 5870 (2018/04/17)
We have developed a reductive carbonylation method by which unactivated alkyl iodides can be hydroxymethylated to provide one-carbon-extended alcohol products under Cu-catalyzed conditions. The method is tolerant of alkyl β-hydrogen atoms, is robust towards a wide variety of functional groups, and was applied to primary, secondary, and tertiary alkyl iodide substrates. Mechanistic experiments indicate that the transformation proceeds by atom-transfer carbonylation (ATC) of the alkyl iodide followed in tandem by two CuH-mediated reductions in rapid succession. This radical mechanism renders the Cu-catalyzed system complementary to precious-metal-catalyzed reductive carbonylation reactions.
Optimization of the alkyl side chain length of fluorine-18-labeled 7α-alkyl-fluoroestradiol
Okamoto, Mayumi,Shibayama, Hiromitsu,Naka, Kyosuke,Kitagawa, Yuya,Ishiwata, Kiichi,Shimizu, Isao,Toyohara, Jun
, p. 512 - 519 (2016/06/14)
Introduction: Several lines of evidence suggest that 7α-substituted estradiol derivatives bind to the estrogen receptor (ER). In line with this hypothesis, we designed and synthesized 18F-labeled 7α-fluoroalkylestradiol (Cn-7α-[18F]FES) derivatives as molecular probes for visualizing ERs. Previously, we successfully synthesized 7α-(3-[18F]fluoropropyl)estradiol (C3-7α-[18F]FES) and showed promising results for quantification of ER density in vivo, although extensive metabolism was observed in rodents. Therefore, optimization of the alkyl side chain length is needed to obtain suitable radioligands based on Cn-7α-substituted estradiol pharmacophores. Methods: We synthesized fluoromethyl (23; C1-7α-[18F]FES) to fluorohexyl (26; C6-7α-[18F]FES) derivatives, except fluoropropyl (C3-7α-[18F]FES) and fluoropentyl derivatives (C5-7α-[18F]FES), which have been previously synthesized. In vitro binding to the α-subtype (ERα) isoform of ERs and in vivo biodistribution studies in mature female mice were carried out. Results: The in vitro IC50 value of Cn-7α-FES tended to gradually decrease depending on the alkyl side chain length. C1-7α-[18F]FES (23) showed the highest uptake in ER-rich tissues such as the uterus. Uterus uptake also gradually decreased depending on the alkyl side chain length. As a result, in vivo uterus uptake reflected the in vitro ERα affinity of each compound. Bone uptake, which indicates de-fluorination, was marked in 7α-(2-[18F]fluoroethyl)estradiol (C2-7α-[18F]FES) (24) and 7α-(4-[18F]fluorobutyl)estradiol (C4-7α-[18F]FES) (25) derivatives. However, C1-7α-[18F]FES (23) and C6-7α-[18F]FES (26) showed limited uptake in bone. As a result, in vivo bone uptake (de-fluorination) showed a bell-shaped pattern, depending on the alkyl side chain length. C1-7α-[18F]FES (23) showed the same levels of uptake in uterus and bone compared with those of 16α-[18F]fluoro-17β-estradiol. Conclusions: The optimal alkyl side chain length of 18F-labeled 7α-fluoroalkylestradiol was the shortest: C1-7α-[18F]FES. Our results indicate that shorter chain lengths within the 4-? ligand binding cavities of ERα are suitable for 7α-fluoroalkylestradiol derivatives.
Palladium-Catalyzed Asymmetric α-Arylation of Alkylnitriles
Jiao, Zhiwei,Chee, Kwok Wei,Zhou, Jianrong Steve
supporting information, p. 16240 - 16243 (2016/12/27)
Asymmetric arylation of alkylnitriles forms quaternary stereocenters in good enantiocontrol for the first time. A lithium heterodimer consisting of an alkylnitrile anion and a disilylamide ion is the actual species responsible for the stereodetermining transmetalation in the catalytic cycle.
Batch to flow deoxygenation using visible light photoredox catalysis
Nguyen, John D.,Reiss, Barbara,Dai, Chunhui,Stephenson, Corey R. J.
, p. 4352 - 4354 (2013/06/05)
Herein we report a one-pot deoxygenation protocol for primary and secondary alcohols developed via the combination of the Garegg-Samuelsson reaction, visible light-photoredox catalysis, and flow chemistry. This procedure is characterized by mild reaction conditions, easy-to-handle reactants and reagents, excellent functional group tolerance, and good yields.
Halogenation of primary alcohols using a tetraethylammonium halide/[Et 2NSF2]BF4 combination
Pouliot, Marie-France,Mahe, Olivier,Hamel, Jean-Denys,Desroches, Justine,Paquin, Jean-Francois
supporting information, p. 5428 - 5431,4 (2020/10/15)
The halogenation of primary alcohols is presented. The use of a combination of tetraethylammonium halide and [Et2NSF2]BF4 (XtalFluor-E) allows for chlorination and bromination reactions to proceed efficiently (up to 92% yield) with a wide range of alcohols. Iodination reactions are also possible albeit in lower yields.
Synthesis of all the stereoisomers of 6-methyl-2-octadecanone, 14-methyl-2-octadecanone, and 6,14-dimethyl-2-octadecanone, sex pheromone components of the Lyclene dharma dharma moth, from the enantiomers of citronellal
Shikichi, Yasumasa,Mori, Kenji
, p. 1943 - 1951 (2013/01/15)
The enantiomers of citronellal were converted to all the stereoisomers of 6-methyl-2-octadecanone, 14-methyl-2-octadecanone, and 6,14-dimethyl-2- octadecanone, the female-produced sex pheromone components of the Lyclene dharma dharma moth. Three wellestablished procedures, the Wittig reaction, alkylation of alkynes, and acetoacetic ester synthesis, were employed for the carbon-carbon bond formation to connect the building blocks.
Boryltrihydroborate: Synthesis, structure, and reactivity as a reductant in ionic, organometallic, and radical reactions
Nozaki, Kyoko,Aramaki, Yoshitaka,Yamashita, Makoto,Ueng, Shau-Hua,Malacria, Max,Lacote, Emmanuel,Curran, Dennis P.
supporting information; experimental part, p. 11449 - 11451 (2010/10/04)
Reaction of lithium 1,3-bis(2,6-diisopropylphenyl)-2,3-dihydro-1H-1,3,2- diazaborol-2-ide with borane·THF provides the first boryl-substituted borohydride: lithium [1,3-bis(2,6-diisopropylphenyl)-2,3-dihydro-1H-1,3,2- diazaborol-2-yl]trihydroborate. The c
Stereoselective total synthesis of (-)-pyrenophorol
Yadav,Subba Reddy,Subba Reddy
scheme or table, p. 5984 - 5986 (2010/02/28)
An efficient stereoselective total synthesis of (-)-pyrenophorol 1 is described. The key steps involved in this synthesis are hydrolytic kinetic resolution (HKR), MacMillan α-hydroxylation, Horner-Wadsworth-Emmons (HWE) reaction, and Mitsunobu cyclization
Synthesis of 7α-substituted derivatives of 17β-estradiol
Jiang, Xiang-Rong,Walter Sowell,Zhu, Bao Ting
, p. 334 - 342 (2007/10/03)
Estrogen receptor (ER) pure antagonists such as ICI-182,780 (fulvestrant) are effective alternatives to tamoxifen (an ER antagonist/weak partial agonist) in the treatment of postmenopausal, receptor-positive human breast cancers. Structurally, these pure
