20731-23-1Relevant articles and documents
A significant effect of triflic acid on the hypervalent λ(n)-iodane- mediated fragmentation of the tertiary cyclopropanol system
Kirihara, Masayuki,Yokoyama, Satoshi,Momose, Takefumi
, p. 1947 - 1956 (1998)
Trifluoromethanesulfonic acid enhanced the ring cleavage in the reaction of silyl tertiary cyclopropyl ethers with phenyliodine(III) diacetate in a catalytic amount.
Preparation of ω-hydroxynonanoic acid and its ester derivatives
Kula, Jozef,Smigielski, Krzysztof,Quang, Thuat B.,Grzelak, Iwona,Sikora, Magdalena
, p. 811 - 817 (1999)
Methyl ricinoleate was ozonized in methanol or in acetic acid and the intermediate hydroperoxides were reduced electrochemically on Pb-cathode to give 9-hydroxynonanoic acid 1 in high yields. The acid 1 was also prepared by direct castor oil ozonolysis in methanol followed by sodium borohydride reduction of the intermediate hydroperoxides. The cost of the electricity for the electroreduction was at least 30 times lower as compared with sodium borohydride consumption. 9-Hydroxynonanoic acid was then transformed to alkyl 9-acetoxynonanoates 3a-3d, for which 1H nuclear magnetic reasonance, mass, and infrared spectra are given. Esterification of the hydroxy acid 1 with boric acid and pyrolysis of the resultant orthoborates produced 8-nonenoic acid 4 in a 45% yield. Reaction of 4 with lower aliphatic alcohols in presence of Amberlyst 15 produced alkyl 8-noneates 5a-5d along with some amounts of a cis/trans mixture of alkyl 7-noneates.
Nickel-mediated reductive coupling of neopentyl bromides with activated alkenes at room temperature and its synthetic application
Ouyang, Yan,Peng, Yu,Li, Wei-Dong Z.
, p. 4486 - 4496 (2019/07/05)
Reductive coupling of sterically hindered neopentyl bromides with activated alkenes mediated by the in situ generated Ni(0) complexes along with some feedstock is achieved in good yield under the mild conditions. This practically useful method of C(sp3)?C(sp3) bond formation provides a complementary approach to the traditional conjugate addition of preformed organometallic reagents to electrophilic olefins, which often requires cryogenic temperature and rigorous exclusion of air and moisture. The robust application of this reductive coupling reaction was demonstrated in a formal synthesis of stereodivergent (?)-copacamphor and (?)-ylangocamphor, which are valuable intermediates for a class of tricyclo[5.3.0.03,8]decane sesquiterpenes. Moreover, this convenient protocol resulted in a facile access to the homolog of Corey aldehyde en route to prostaglandins, implying the possible involvement of radical-like species.
SYNTHESIS OF PHEROMONES AND RELATED MATERIALS VIA OLEFIN METATHESIS
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, (2018/09/12)
Methods for preparation of olefins, including 8- and 11-unsaturated monoenes and polyenes, via transition metathesis-based synthetic routes are described. Metathesis reactions in the methods are catalyzed by transition metal catalysts including tungsten-, molybdenum-, and ruthenium-based catalysts. The olefins include insect pheromones useful in a number of agricultural applications.
FLOUROALKYL, FLOUROALKOXY, PHENOXY, HETEROARYLOXY, ALKOXY, AND AMINE 1,4-BENZOQUINONE DERIVATIVES FOR TREATMENT OF OXIDATIVE STRESS DISORDERS
-
, (2017/07/14)
Disclosed herein are compounds and methods of using such compounds for treating or suppressing oxidative stress disorders, including mitochondrial disorders, impaired energy processing disorders, neurodegenerative diseases and diseases of aging, or for modulating one or more energy biomarkers, normalizing one or more energy biomarkers, or enhancing one or more energy biomarkers, wherein the compounds are tocopherol quinone derivatives. Further disclosed are compounds, compositions, and methods for treatment of, or prophylaxis against, radiation exposure.
Z -selective ethenolysis with a ruthenium metathesis catalyst: Experiment and theory
Miyazaki, Hiroshi,Herbert, Myles B.,Liu, Peng,Dong, Xiaofei,Xu, Xiufang,Keitz, Benjamin K.,Ung, Thay,Mkrtumyan, Garik,Houk,Grubbs, Robert H.
supporting information, p. 5848 - 5858 (2013/05/22)
The Z-selective ethenolysis activity of chelated ruthenium metathesis catalysts was investigated with experiment and theory. A five-membered chelated catalyst that was successfully employed in Z-selective cross metathesis reactions has now been found to be highly active for Z-selective ethenolysis at low ethylene pressures, while tolerating a wide variety of functional groups. This phenomenon also affects its activity in cross metathesis reactions and prohibits crossover reactions of internal olefins via trisubstituted ruthenacyclobutane intermediates. In contrast, a related catalyst containing a six-membered chelated architecture is not active for ethenolysis and seems to react through different pathways more reminiscent of previous generations of ruthenium catalysts. Computational investigations of the effects of substitution on relevant transition states and ruthenacyclobutane intermediates revealed that the differences of activities are attributed to the steric repulsions of the anionic ligand with the chelating groups.
Iron-catalyzed decarbonylation reaction of aliphatic carboxylic acids leading to α-olefins
Maetani, Shinji,Fukuyama, Takahide,Suzuki, Nobuyoshi,Ishihara, Daisuke,Ryu, Ilhyong
scheme or table, p. 2552 - 2554 (2012/03/26)
The catalytic decarbonylation reaction of aliphatic carboxylic acids can be carried out in the presence of an iron complex, and it proceeds smoothly to give α-olefins with high selectivity. The Royal Society of Chemistry 2012.
Efficient iridium-catalyzed decarbonylation reaction of aliphatic carboxylic acids leading to internal or terminal alkenes
Maetani, Shinji,Fukuyama, Takahide,Suzuki, Nobuyoshi,Ishihara, Daisuke,Ryu, Ilhyong
experimental part, p. 1389 - 1394 (2011/04/25)
Vaska's complex, IrCl(CO)(PPh3)2, when combined with KI as an additive, served as an excellent catalyst for the decarbonylation of long-chain aliphatic carboxylic acids to give internal alkenes with high selectivity. On combination with KI and Ac2O as additives under controlled temperatures, decarbonylation proceeded to give terminal alkenes with high selectivity.
Remote supramolecular control of catalyst selectivity in the hydroformylation of alkenes
Dydio, Pawea,Dzik, Wojciech I.,Lutz, Martin,De-Bruin, Bas,Reek, Joost N. H.
supporting information; experimental part, p. 396 - 400 (2011/03/16)
In the pocket: The supramolecular interactions between a Rh phosphine catalyst equipped with an anion-binding pocket and alkenes that contain anionic functionalities (see picture) provide an excellent design concept to achieve remote control of the regioselectivity in hydroformylation reactions. The 4-pentenoate and 3-butenylphosphonate, which fit tightly between the Rh center and the pocket, were hydroformylated with unprecedented selectivity.
Construction of carbo- And heterocycles using radical relay cyclizations initiated by alkoxy radicals
Zhu, Hai,Wickenden, Jason G.,Campbell, Natalie E.,Leung, Joe C. T.,Johnson, Kayli M.,Sammis, Glenn M.
supporting information; experimental part, p. 2019 - 2022 (2009/09/08)
An efficient method for the rapid construction of carbo- and heterocycles has been developed using radical relay cyclizations initiated by alkoxy radicals. Linear substrates were cyclized to form a wide range of cyclopentane, pyrrolidine, tetrahydropyran, and tetrahydrofuran derivatives in excellent yields. This methodology was utilized as a key step in the synthesis of the tetrahydrofuran fragment in (-)-amphidino-lide K.
