4736-60-1Relevant academic research and scientific papers
Enzymatic Synthesis of Methylated Terpene Analogues Using the Plasticity of Bacterial Terpene Synthases
Dickschat, Jeroen S.,Hou, Anwei,Lauterbach, Lukas
, (2020)
Methylated analogues of isopentenyl diphosphate were synthesised and enzymatically incorporated into methylated terpenes. A detailed stereochemical analysis of the obtained products is presented. The methylated terpene precursors were also used in conjunction with various isotopic labellings to gain insights into the mechanisms of their enzymatic formation.
Quaternary Phosphorus-Induced Iodocuprate(I)-Based Hybrids: Water Stabilities, Tunable Luminescence and Photocurrent Responses
Zhang, Wen-Ting,Liu, Jian-Zhi,Liu, Jing-Bo,Song, Kai-Yue,Li, Yi,Chen, Zhi-Rong,Li, Hao-Hong,Jiang, Rong
supporting information, p. 4234 - 4244 (2018/10/15)
Four (triphenyl)phosphonium-based quaternary phosphorus salts with different substituents (varying from methyl to n-butyl) were selected to be structural directed agents (SDAs) to construct four iodocuprate(I) hybrids via solution method, i.e., [(PPh3Me)(Cu3I4)]n (1), [(PPh3Et)(Cu3I4)]n (2), (PPh3iPr)2(Cu2I4) (3), [(PPh3nBu)(Cu3I4)]n (4). The inorganic iodocuprates in 1, 2 and 4 are 1-D (Cu3I4)nn– chains constructed from Cu5I11 units, but (Cu2I4)2– in 3 is a di-nuclear cluster. Interestingly, the strength of Cu···Cu and π–π stacking interactions are weakened with the lengthening of alkyl groups on P-atom. The best water stability of 4 can be ascribed to the better hydrophobicity of n-butyl group, which deters the dispersing of organic and inorganic moieties and as a result, inhibit hydrolysis reaction. Furthermore, all compounds exhibit typical reversible luminescent thermochromic behaviors, among which 4 exhibits blue emission and the quenching of higher energy (HE) zone in 1 and 2 are led by strong π–π stacking interactions. Besides, effective and repeatable photocurrent responses can be detected in these compounds. In all, by systematically introducing alkyl groups into (triphenyl)phosphonium as SDAs to prepare hybrid iodocuprates, we can find that the longer alkyl groups can achieve stronger tunable PL materials with enhanced water stabilities.
Enantioselective palladium-catalyzed addition of malonates to 3,3-difluoropropenes
Drouin, Myriam,Paquin, Jean-Fran?ois
supporting information, p. 6023 - 6032 (2018/09/11)
Monofluoroalkenes bearing a malonate unit at the β position can be synthesized by the enantioselective addition of diesters to 3,3-difluoropropenes. The difference in reactivity regarding the geometry and the substituents of the alkene of the 3,3-difluoropropenes, as well as the alkyl groups of the malonates, was studied and limitations were identified. The reaction was also performed with different 3,3-difluoropropenes. Further synthetic transformations of a newly functionalized monofluoroalkene were also accomplished.
(E)-Selective Wittig Reactions between a Nonstabilized Phosphonium Ylide Bearing a Phosphastibatriptycene Skeleton and Benzaldehydes
Uchiyama, Yosuke,Ohtsuki, Takemaru,Murakami, Rikiya,Shibata, Munenori,Sugimoto, Jun
, p. 159 - 174 (2017/01/14)
Wittig reactions between benzaldehyde derivatives and a nonstabilized phosphonium ylide bearing a phosphastibatriptycene skeleton, regarded as a tridentate aryl ligand, gave (E)-alkenes with high selectivity in the presence of both lithium and sodium salts. As previously reported, reactions between a triphenylphosphonium ylide and benzaldehyde derivatives under the same conditions afforded mainly (Z)-alkenes. Variable-temperature (VT)31P{1H} NMR spectra showed two signals, assigned to cis- and trans-1,2-oxaphosphetanes, which were observed at different temperatures (–80 °C and –40 °C, respectively) in the Wittig reaction between benzaldehyde and the nonstabilized phosphonium ylide bearing the phosphastibatriptycene skeleton, in the presence of both lithium and sodium salts, and showed the existence of equilibrium between these products at –40 °C. On the other hand, this equilibrium was not clearly observed in the reaction between the triphenylphosphonium ylide and benzaldehyde, for which only one signal was detected. The observed intermediates were confirmed to be 1,2-oxaphosphetanes by deprotonation of the isolated β-hydroxyalkylphosphonium salts bearing a phosphastibatriptycene skeleton and a triphenylphosphine moiety, respectively. Crossover reactions were conducted in the deprotonations of β-hydroxyalkylphosphonium salts with TMS2NNa in the presence of p-chlorobenzaldehyde, resulting in the observation of signals corresponding to 1,2-oxaphosphetanes containing phenyl and p-chlorophenyl groups at the 4-positions, indicating the exchange process between benzaldehyde and p-chlorobenzaldehyde at –40 °C for the phosphastibatriptycene system and at 0 °C for triphenyl derivatives. These results clearly indicated that stereochemical drift occurred at those temperatures, even in reactions using nonstabilized phosphonium ylides. The stereochemical drift in the phosphastibatriptycene system occurred at a lower temperature than in the case of the triphenyl derivative, thus explaining the (E)-selective Wittig reactions between the benzaldehyde derivatives and the nonstabilized phosphastibatriptycene-based phosphonium ylide in the presence of lithium and sodium salts.
Design, synthesis and SAR study of novel sulfonylureas containing an alkenyl moiety
Wei, Wei,Cheng, Dandan,Liu, Jingbo,Li, Yuxin,Ma, Yi,Li, Yonghong,Yu, Shujing,Zhang, Xiao,Li, Zhengming
, p. 8356 - 8366 (2016/09/09)
A series of sulfonylurea compounds was designed and synthesized via introducing an alkenyl moiety into the aryl-5 position and most title compounds exhibited enhanced antifungal activities and limited herbicidal activities compared with chlorsulfuron. Then, a CoMSIA calculation for antifungal activities was carried out to establish a 3D-QSAR model in which a cross-validated q2 of 0.585 and a correlation coefficient r2 of 0.989 were obtained. The derived model revealed that hydrophobic and electrostatic fields were the two most important factors for antifungal activity. Structure optimization was performed according to the CoMSIA model and compound 9z was found to be as potent as chlorothalonil in vitro against C. cornigerum, the pathogen of the wheat sharp eyespot disease. In order to study the fungicidal mechanism, 9z was successfully docked into yeast AHAS using a flexible molecular docking method and the resulting binding pattern was similar to that of chlorimuron-ethyl, indicating that the antifungal activity of compounds 9 was probably due to the inhibition of fungal AHAS.
A transition-metal-free Heck-type reaction between alkenes and alkyl iodides enabled by light in water
Liu, Wenbo,Li, Lu,Chen, Zhengwang,Li, Chao-Jun
supporting information, p. 6170 - 6174 (2015/06/08)
A transition-metal-free coupling protocol between various alkenes and non-activated alkyl iodides has been developed by using photoenergy in water for the first time. Under UV irradiation and basic aqueous conditions, various alkenes efficiently couple with a wide range of non-activated alkyl iodides. A tentative mechanism, which involves an atom transfer radical addition process, for the coupling is proposed.
New methodology for the conversion of epoxides to alkenes
Wu, Feng-Ling,Ross, Benjamin P.,McGeary, Ross P.
experimental part, p. 1989 - 1998 (2010/06/15)
Epoxides have been transformed in good yields to alkenes by a process involving (i) ring-opening of the epoxide with 2-mercaptobenzothiazole, (ii) oxidation of the derived ss-hydroxy thioethers to the corresponding sulfones, and (iii) thermal or base-promoted fragmentation of these sulfones to alkenes. The stereochemistry of the starting epoxide is transfer-red faithfully to the alkene product, because of the SN2 epoxide ring-opening reactions and the antiperiplanar SO2 elimination reaction of the ss- alkoxysulfinate intermediates. This methodology may form the basis of a new protecting group strategy for alkenes.
Highly selective iridium-catalyzed asymmetric hydrogenation of trifluoromethyl olefins: A new route to trifluoromethyl-bearing stereocenters
Engman, Mattias,Cheruku, Pradeep,Tolstoy, Paeivi,Bergquist, Jonas,Voelker, Sebastian F.,Andersson, Pher G.
supporting information; experimental part, p. 375 - 378 (2009/11/30)
Fluorine-containing compounds are useful in many applications ranging from pharmaceuticals to ferroelectric crystals. We have developed a new, highly enantioselective synthetic route to trifluoromethyl-bearing stereocenters in up to 96% ee via asymmetric hydrogenation using N,P-ligated iridium catalysts. We also hydrogenated an isomeric mixture of olefins; this reaction gave the hydrogenation product highly enantioselectively (87% ee), and only the E isomer was present after the reaction had reached 56% conversion.
Iridium-catalyzed asymmetric hydrogenation yielding chiral diarylmethines with weakly coordinating or noncoordinating substituents
Tolstoy, Paeivi,Engman, Mattias,Paptchikhine, Alexander,Bergquist, Jonas,Church, Tamara L.,Leung, Abby W.-M.,Andersson, Pher G.
supporting information; experimental part, p. 8855 - 8860 (2009/12/04)
Diarylmethine-containing stereocenters are present in pharmaceuticals and natural products, making the synthetic methods that form these chiral centers are important in industry. We have applied iridium complexes with novel N,P-chelating ligands to the asymmetric hydrogenation of trisubstituted olefins, forming diarylmethine chiral centers in high conversions and excellent enantioselectivities (up to 99% ee) for a broad range of substrates. Our results support the hypothesis that steric hindrance in one specific area of the catalyst is playing a key role in stereoselection, as the hydrogenation of substrates differing little at the prochiral carbon occurred with high enantioselectivity. As a result, excellent stereodiscrimination was obtained even when the prochiral carbon bore, for example, phenyl and p-tolyl groups.
Synthesis of the deuterated sex pheromone components of the grape borer, xylotrechus pyrrhoderus
Kiyota, Ryutaro,Yamakawa, Rei,Iwabuchi, Kikuo,Hoshino, Keita,Ando, Tetsu
experimental part, p. 2252 - 2256 (2010/08/03)
Adult males of the grape borer, Xylotrechus pyrrho- derus, secrete (S)-2-hydroxy-3-octanone [(S)-1] and (2S,3S)-2,3-octanediol [(2S,3S)-2] from their nota of prothoraces as sex pheromone components. Their structural similarity suggests that one of them is the biosynthetic precursor of the other component. In order to confirm the biochemical conversion, deuterated derivatives of both components were synthesized by starting from a Wittig reaction between hexanal and an ylide derived from D5-iodoethane and ending with enantiomeric resolution by chiral HPLC. The molecular ions of 1 and 2 could scarcely be detected by using a GC- MS analysis, and the labeled compounds showed similar mass spectra to the unlabeled pheromone components. However, several fragment ions, including four deuterium atoms, were observed in the mass spectra of their acetate derivatives, indicating that the conversion could be confirmed by examining a compound with the diagnostic ions after acetylation of the volatiles collected from insects treated with the labeled precursors.
