- Influence of n Si/n Al ratio of HY zeolite catalysts on alkylation of toluene with tert-butanol
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The highly selective synthesis of 4-tert-butyltoluene from toluene and tert-butanol over HY zeolites was performed in liquid phase. The effect of Si/Al ratio (6.3, 7.5, 11, 12) of HY zeolites on the alkylation performance was studied. The catalysts were characterized by SEM, XRD, FT-IR, and NH3-TPD methods. With increase of Si/Al ratio, the conversion of toluene and the selectivity towards 4-tert-butyltoluene increased gradually. HY-12 was found to be more suitable for the tert-butylation of toluene. When the alkylation reaction was conducted at 180°C for 4 h using HY-12 catalyst, the conversion and the selectivity of 4-tertbutyltoluene reached 40.74 and 70.91%, respectively.
- Wang, Yuanyuan,Song, Hua,Sun, Xinglong,Song, Hua Lin
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- Tert-Butylation of toluene with tert-butyl alcohol over immobilized titanium species on the Al-MCM-48
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A series of Ti-Al-M48 (M48 stand for MCM-48) samples with different titanium species loadings were prepared by immobilization method. Their physical chemical properties were characterized by XRD, liquid N2 adsorption-desorption, Py-IR, NH3-TPD and UV-vis DRS techniques, and their catalytic performances were investigated in the tert-butylation of toluene with tert-butyl alcohol in a 100 ml stainless steel autoclave equipped with a magnetically driven impeller. The Ti-Al-M48 samples have a large BET surface and ordered mesoporous structure. Although the titanium species loading is the same, the 4% Ti-Al-M48 sample has a larger acid amount than the 4% Ti/Al-M48 sample prepared by impregnation. The Py-IR and UV-vis DRS spectra revealed that the isolated TiO4 tetrahedra by isomorphous substitution into the Al-M48 network have Lewis acidity. The 4% Ti-Al-M48 has a higher catalytic performance than other samples and the influence of reaction conditions on the tert-butylation of toluene was discussed. The conversion of toluene is 47.5% and the selectivity of p-tert-butyltoluene is 77.2% at the molar ratio of tert-butyl alcohol to toluene 2, the weight ratio of toluene to catalyst 8, reaction temperature 453K and reaction time 4 h. The 4% Ti-Al-M48 sample shows high stability, and toluene conversion 43.7% and p-tert-butyltoluene selectivity 78.4% can be obtained even though after repeated reaction for 3 times.
- Zhou, Zhiwei,Mao, Wei,Qin, Juan,Han, Tianpeng,Han, Chaofan,Wu, Wenliang
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- Tert-butylation of toluene with tert-butanol over transition metal oxide-modified HBEA zeolite
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A series of transition metal oxide-modified HBEA (MxOy/HBEA) zeolite catalysts were prepared by the wetness impregnation method, and investigated for the alkylation of toluene with tert-butanol to synthesise 4-tert-butyltoluene (4-TBT). Their physico-chemical properties were characterised by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller and NH3 temperature-programmed desorption methods. MxOy/HBEA zeolite showed higher para-selectivity than parent HBEA due to its improved structural and acidic properties. Though the toluene conversion of MxOy/HBEA catalyst decreased, the 4-TBT selectivity increased significantly at 190 °C after 4 h. The narrowed pores after loading the MxOy prompted an increase in selectivity for 4-TBT by increasing the shape selectivity. In addition, the decrease in strong acid sites increased selectivity for 4-TBT by suppressing further isomerisation of the 4-TBT formed on acid sites. Among all the modified HBEA zeolites, Fe2O3/HBEA exhibited the best catalytic activity and para-selectivity. The factors affecting the reaction over Fe2O3/HBEA have also been investigated extensively.
- Han, Yixian,Song, Hua,Wang, Yuanyuan,Sun, Xinglong,Sun, Zhigang
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- Alkylation of toluene with tert-butyl alcohol over HPW-modified HΒ zeolite
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An Hβ-supported heteropoly acid (H3PW12O40(HPW)/Hβ) catalyst was successfully prepared by wetness impregnation, and investigated in the alkylation of toluene with tert-butyl alcohol for the synthesis of 4-tert-butyltoluene (PTBT). X-ray diffraction, scanning electron microscopy, transmission electron microscopy, fourier-transform infrared spectroscopy, inductively coupled plasma-optical emission spectrometry, the brunauer emmett teller (BET) method, temperature-programmed NH3desorption, and pyridine adsorption infrared spectroscopy were used to characterize the catalyst. The results showed that loading HPW on Hβ effectively increased the B acidity and decreased the pore size of Hβ. The B acidity of HPW/Hβ was 142.97 μmol/g, which is 69.74% higher than that of Hβ (84.23 μmol/g). The catalytic activity of the HPW/Hβ catalyst was much better than that of the parent Hβ zeolite because of its high B acidity. The toluene conversion over HPW/Hβ reached 73.1%, which is much higher than that achieved with Hβ (54.0%). When HPW was loaded on Hβ, the BET surface area of Hβ decreased from 492.5 to 379.6 m2/g, accompanied by a significant decrease in the pore size from 3.90 to 3.17 nm. Shape selectivity can therefore play an important role and increase the product selectivity of the HPW/Hβ catalyst compared with that of the parent Hβ. PTBT (kinetic diameter 0.58 nm) can easily diffuse through the narrowed pores of HPW/Hβ, but 3-tert-butyltoluene (kinetic diameter 0.65 nm) diffusion is restricted because of steric hindrance in these narrow pores. This results in high PTBT selectivity over HPW/Hβ (around 81%). The HPW/Hβ catalyst gave a stable catalytic performance in reusability tests.
- Wang, Yuanyuan,Song, Hua,Sun, Xinglong
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- A process scheme involving transalkylation reactions to prepare o-bromophenol from phenol
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The bromination of phenol to o-bromophenol was carried out by protecting the para position with a tert-butyl group. The latter group was subsequently transferred to toluene using aluminum chloride as a catalyst. The resulting mixture of p-and m-tert-butyltoluene could be converted back to p-tert-butylphenol by transalkylation of the former with phenol in the presence of Engelhard, F-24. Thus, a process scheme based on transalkylation reactions as the intermediate steps has been proposed to synthesize o-bromophenol from phenol via p-tert-butylphenol. The effect of reaction parameters on overall conversion to and selectivity with respect to the desired product was studied for the transalkylation reactions involved in the process.
- Trivedi, Nikhil R.,Chandalia, Sampatraj B.
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- Electrophilic Aromatic Substitution. 10. A Kinetic Study of the Friedel-Crafts tert-Butylation Reaction in Nitromethane
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A kinetic study of the reaction between tert-butyl chloride and benzene or toluene using aluminum chloride as catalyst was made in solvent nitromethane over the temperature range -27 to 10 deg C.The rate law was found to be first order in aromatic hydrocarbon, in tert-butyl chloride and in initial catalyst concentration.At -15 deg C k3 for benzene = 6.7 (+/-1.0) * 10-2M-2s-1; for toluene k3 = 20 (+/-2)*10-1M-2s-1 with product isomer percentages meta 4.6 +/- 0.3 and para 95.4 +/- 0.3.Ea is 76 +/- 13 kJ/mol, ΔH = 74 +/- 13 kJ/mol, and ΔS = 16 +/- 46 J/deg mol.Competitive results were kT/kB = 25 +/- 1, 4.9 +/- 0.1percent meta, 95.1 +/- 0.1percent para.The results fit Brown's selectivity relationship.A mechanism involving a rate-determining attack by a tert-butyl cation-AlCl4- ion pair on the aromatic is proposed.
- DeHaan, Franklin P.,Chan,Wai H.,Chang, Jeffrey,Ferrara, Daro M.,Wainschel, Larry A.
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- Alkylation of Toluene with tert-Butyl Alcohol over Different Zeolites with the Same Si/Al Ratio
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Three zeolites (Beta, Mordenite and ZSM-5), with different pore channels but the same Si/Al ratio (25), were applied as catalysts to evaluate the effects of acidity and channel structure on the catalytic activity for toluene butylation at 180°C in an automated high-pressure stainless steel reactor. The same Si/Al ratio of the three zeolites resulted to different catalytic activity, since both acidity and channel structures of zeolites influenced catalytic activity. Zeolite Beta possessing a three-dimensional, 12-ring channel system, the smallest crystal size and larger amount of B acid sites demonstrated the highest toluene conversion (54percent). Mordenite, with 32.7percent toluene conversion, exhibited higher para-selectivity than Beta, which could be explained by the shape-selective catalysis. ZSM-5 with the largest amount of B acid sites presented the lowest catalytic activity, since alkylation can occur only on the surface active sites.
- Han, Yixian,Song, Hua,Sun, Xinglong,Wang, Wenyi,Wang, Xueqin,Wang, Yuanyuan,Zhang, Jiaojing
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- Preparation of H-mordenite/MCM-48 composite and its catalytic performance in the alkylation of toluene with tert-butanol
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A series of HM/MCM-48 samples with different SiO2/Al2O3 molar ratio were prepared by sol-gel method. The prepared catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, FT-IR, SEM, and TEM techniques, and their catalytic performance was investigated in alkylation of toluene with tert-butanol. The adsorption capacity and the acid sites amount of HM/MCM-48-4 sample prepared by growing MCM-48 on the surface of HM zeolite are much higher than that of their mechanical mixture (HM/MCM-48(4) sample) due to its biporous structure; it shows higher catalytic performance than other HM/MCM-48 samples. The influence of reaction conditions on the catalytic performance of HM/MCM-48-4 zeolite was discussed. Toluene conversion of 41.4% and p-tert-butyltoluene selectivity of 73.5% were obtained at the weight ratio of toluene to HM/MCM-48-4 of 5, reaction temperature of 453 K, reaction time of 5 h and the molar ratio of toluene to tert-butanol of 0.5.
- Zhou, Zhiwei,Cheng, Fuling,Qin, Juan,Yu, Pengcheng,Xu, Lin,Gu, Zhiqiang,Liu, Xiaoqin,Wu, Wenliang
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- Thermochemical properties of branched alkylsubstituted benzenes
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The standard (p○ = 0.1 MPa) molar enthalpies of formation ΔfH○m (1 or cr) at the temperature T = 298.15 K were measured using combustion calorimetry for tert-butylbenzene, 4-methyl-1-tert-butylbenzene, 3,5-dimethyl - tert-butylbenzene, 5-methyl-1,3-di-tert-butylbenzene, and 1,4-di-tert-butylbenzene. The standard molar enthalpies of vaporization Δg1H○m, or sublimation ΔgcrH○m, of these compounds, and also of 3-methyl-1-tert-butylbenzene, 1,3-di-tert-butylbenzene, and 1,3,5-tri-tert-butylbenzene were obtained from the temperature function of the vapour pressure measured in a flow system. Enthalpies of fusion Δ1crH○m of solid compounds were measured by d.s.c. Strain enthalpies of branched alkylbenzenes were derived from the measured enthalpies of formation of the gaseous compounds. These experimental results, together with the data available from the literature, provided a quantitative understanding of the interrelations of structure and energetics of alkylbenzenes, and a further improvement on the group-contribution methodologyfor estimation of thermodynamic properties of organic compounds.
- Verevkin, Sergey P.
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- Friedel-Crafts alkylation of toluene with tert-butyl alcohol over Fe2O3-modified Hβ
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Fe2O3 (x)/Hβ catalysts with different Fe2O3 loadings (x) were successfully prepared and characterized by XRD, SEM, TEM, ICP, BET, NH3-TPD and Py-IR. With selective alkylation of toluene with tert-butyl alcohol to produce 4-tert-butyltoluene as a probe reaction, the effects of the different Fe2O3 loadings on channel structures, acidity and catalytic performance over Hβ were studied. The results showed that modification of Hβ with Fe2O3 could adjust pore structures and decrease the total acidity, especially the strong acidity of Hβ. The parent Hβ exhibited the highest toluene conversion of 58.4% with the lowest PTBT selectivity of 67.3%. The low para-selectivity over parent Hβ could be attributed to the low shape-selective action of 12-ring portals of Hβ and the isomerization of the formed PTBT to MTBT. Upon loading of Fe2O3, the toluene conversion of Fe2O3 (x)/Hβ catalysts decreased slightly, but the PTBT selectivity increased significantly. A toluene conversion of 54.7% with PTBT selectivity of 81.5% was observed over Fe2O3 (20%)/Hβ at 190 °C after 4 h. The narrowed pores after loading the Fe2O3 were beneficial to increasing the selectivity to PTBT, since PTBT with a lower kinetic diameter (0.58 nm) can diffuse through the narrowed pores of Fe2O3 (x)/Hβ more easily than MTBT (0.65 nm). In addition, the decrease in number of strong acid sites and deactivation of acid sites on the surface are beneficial to increasing the selectivity to PTBT by suppressing further isomerization of the formed PTBT on acid sites.
- Wang, Yuanyuan,Song, Hua,Sun, Xinglong
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p. 107239 - 107245
(2016)
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- tert-Butylation of Toluene Catalyzed by Phosphotungstic Acid Supported on HBEA Zeolite
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Abstract: The performance of the catalysts prepared by impregnation of phosphotungstic acid (HPW) in HBEA zeolite with different HPW load (HPW(x)/HBEA) was evaluated in alkylation of toluene with tert-butanol with formation of 4-tert-butyltoluene (4-TBT). The obtained results showed that the HPW was highly dispersed on the HBEA support. The specific surface area of HPW(x)/HBEA zeolites decreased along with a decrease in pore volume. The Br?nsted acidity of HPW(x)/HBEA showed a significant increase initially, reaching a maximum at x = 30% and then decreased with further increasing x. The Br?nsted acidity of HPW(30%)/HBEA was 143.0 μmol/g, which is an increase of 69.8% when compared with that found for HBEA (84.2 μmol/g). The HPW(x)/HBEA zeolite with HPW loading of 30% exhibits the best catalytic activity at 180°C after 4 h. Toluene conversion over HPW(30%)/HBEA reached 73.1% with para-selectivity of 80.9%, which much higher than those found for HBEA (activity of 54.0% with para-selectivity of 69.5%). The improved toluene conversion over HPW(x)/HBEA can be attributed to their higher Br?nsted acidity after loading HPW, while the improved selectivity can be attributed to the narrowed pores of HPW(x)/HBEA catalysts.
- Yuanyuan Wang,Han, Yixian,Sun, Xinglong,Song, Hua
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- Framework-Substituted Sn-MOR Zeolite Prepared by Multiple pH-Adjusting Сo-Hydrolysis As Efficient Catalyst for tert-Butylation of Toluene
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Abstract: A series of Sn-MOR samples with different tin species loadings were prepared via a mutiple pH?adjusting co-hydrolysis method. Their properties were characterized by XRD, XRF, UV–Vis, FT-IR, Py-IR, N2 sorption and SEM techniques. The catalytic performance was evaluated in liquid-phase toluene alkylation with tert-butyl alcohol. The characterization results shows that compared to framework destruction of mordenite for the Sn/MOR sample with floccule prepared by ion exchange method, higher relative crystallinity and larger surface area and pore volume for Sn-MOR samples with walnut morphology can be obtained. The doping with tin species can increase the Lewis acidity and decrease the pore size resulting in both higher toluene conversion and p-tert-butyltoluene (PTBT) selectivity. The Sn-MOR(0.010) sample shows the highest catalytic performance with toluene conversion of 48.0% and PTBT selectivity of 85.6%. It?shows high stability: toluene conversion of 45.3% and PTBT selectivity of 87.2% can be obtained even after 5 consecutive runs.
- Fuling Cheng,Zhou, Zhiwei,Qin, Juan,Li, Dong,Wang, Jianzong,Wu, Wenliang
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- HIGH CATALYTIC ACTIVITY OF IRON OXIDE FOR BENZYLATION, t-BUTYLATION, AND ACETYLATION OF TOLUENE WITH BENZYL, t-BUTYL, AND ACETYL CHLORIDES
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Iron oxides obtained by calcining at 300-500 deg C Fe(NO3)3 or iron hydroxides, precipitated by hydrolyzing FeCl3 and Fe(NO3)3 with ammonia, showed exceedingly high catalytic activities for the title reactions at room temperature.
- Arata, Kazushi,Hino, Makoto
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- Temperature Dependence of the Substrate and Positional Selectivity of the Aromatic Substitution by Gaseous tert-Butyl Cation
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The temperature dependence of the substrate and positional selectivity of the alkylation of benzene and toluene by radiolytically formed t-Bu+ ions has been investigated in isobutane gas at 720 torr in the range 0-140 deg C.The Arrhenius plot of the empirical kT/kB ratio is linear over an extended (0-100 deg C) interval, and its slope corresponds to a difference of 3.6 +/- 0.4 kcal mol-1 between the activation energy for the tert-butylation of benzene and of toluene.The positional selectivity of the alkylation is affected by the temperature as well, the p:1/2 m ratio decreasing from ca. 27 at 0 deg C to 7.5 at 140 deg C.The results are interpreted as evidence that under conditions typical of radiolytic experiments the activation mechanism of the addition of t-Bu+ to arenes, a typical ion-molecule reaction, is essentially thermal, as expected at the high-pressure limit of gas-phase ionic processes.
- Cacace, Fulvio,Ciranni, Giovanna
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- Flow Friedel–Crafts alkylation of 1-adamantanol with arenes using HO-SAS as an immobilized acid catalyst
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In this communication flow Friedel–Crafts alkylation was studied using hydroxy-substituted sulfonic acid-functionalized silica as a catalyst and 1-adamantanol as a model substrate. The reaction of 1-adamantanol (1a) with toluene (2a) proceeded well with 5 min of residence time at 120°C to give good yield of 1-tolyladamantane (3a) as a 1:9 mixture of meta and para isomers. When the flow synthesis was carried out over 2.5 hr of running time, the collected five fractions contain the product 3a in 97–92% yields, suggesting the durability of the catalyst.
- Kasakado, Takayoshi,Hyodo, Mamoru,Furuta, Akihiro,Kamardine, Aina,Ryu, Ilhyong,Fukuyama, Takahide
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- Preparation of tin-doped mordenite by multistep pH template-free method for the tert-alkylation of toluene
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Multistep pH template-free method was adopted to the preparation of the tin-doped mordenite (SnMOR) samples with the different framework-substituted tin species loadings, and their physical and chemical properties were studied by different characterizations. Their catalytic performances in the alkylation of toluene with tert-butyl alcohol were also investigated. The characterization results indicated that although the tin species can be incorporated into the framework of mordenite by the substitution of aluminum resulting in the decrease of relative crystallinity, the Lewis acidity would be promoted and the pore size would be dropped resulting in the increase of both toluene conversion and Para-tert-butyltoluene (PTBT) selectivity in the reaction. SnMOR (50) showed the highest catalytic performance, whose toluene conversion of 36.3% and PTBT selectivity of 81.8%, respectively, can be reached. And it showed good catalytic stability, and toluene conversion of 33.7% and PTBT selectivity of 87.2% would be obtained even after reacted for 5 times.
- Li, Yang,Zhou, Zhiwei,Qin, Juan,Liu, Zhirui,Huang, Hao,Liu, Guang,Wu, Wenliang
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p. 485 - 492
(2019/07/31)
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- Surface Modification of a Supported Pt Catalyst Using Ionic Liquids for Selective Hydrodeoxygenation of Phenols into Arenes under Mild Conditions
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The selective and efficient removal of oxygenated groups from lignin-derived phenols is a critical challenge to utilize lignin as a source for renewable aromatic chemicals. This report describes how surface modification of a zeolite-supported Pt catalyst using ionic liquids (ILs) remarkably increases selectivity for the hydrodeoxygenation (HDO) of phenols into arenes under mild reaction conditions using atmospheric pressure H2. Unmodified Pt/H-ZSM-5 converts phenols into aliphatic species as the major products along with a slight amount of arenes (10 % selectivity). In contrast, the catalyst modified with an IL, 1-butyl-3-methylimidazolium triflate, keeps up to 76 % selectivity for arenes even at a nearly complete conversion of phenols. The IL on the surface of Pt catalyst may offer the adsorption of phenols in an edge-to-face manner onto the surface, thus accelerating the HDO without the ring hydrogenation.
- Ohta, Hidetoshi,Tobayashi, Kanako,Kuroo, Akihiro,Nakatsuka, Mao,Kobayashi, Hirokazu,Fukuoka, Atsushi,Hamasaka, Go,Uozumi, Yasuhiro,Murayama, Haruno,Tokunaga, Makoto,Hayashi, Minoru
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supporting information
p. 14762 - 14766
(2019/11/13)
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- Organic metal compounds and organic light emitting diodes comprising the same
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PURPOSE: An organic metal compound is provided to have excellent thermal properties and light emitting efficiency, thereby being useful for a display and lighting device. CONSTITUTION: An organic metal compound is represented by chemical formula 1. In chemical formula 1, each of R and Z is hydrogen, deuterium, cyano, halogen hydroxy, nitro, C1-40 alkyl, C1-40 alkoxy, C1-40 alkylamino, C6-40 arylamino, C3-40 heteroarylamino, C1-40 alkoxy group, C1-40 alkylamino, C6-40 aryl group, C3-40 aryloxy group, germanium, phosphorous, and boron; each of A, B, C, D, and E is a substituted or unsubstituted aromatic cycle, or substituted or unsubstituted hydrocycle, X is carbon or nitrogen, G is chemical bond or C1-4 alkylene which can be substituted by (R-Zi)n.
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Paragraph 0488; 0495; 0498-0500
(2018/12/01)
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- METHOD OF ALKYLATING OR ACYLATING AN ARENE
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A method of alkylating or acylating an arene includes reacting the arene with an organic halide in the presence of an aprotic solvent and a catalyst of formula (I) MR1mXn.Z(R2)(R3)??(I) wherein M is Al, Ga, or Fe; R1 is C1-C12 alkyl; m is 0 or 1; R2 and R3 are each independently unsubstituted or substituted C2-C12 alkyl; each occurrence of X is independently a halogen; n is 2 or 3; the sum of m and n is 3; and Z is S or O. When M is Al, then m is 1, n is 2, and R2 and R3 are each independently substituted with at least one electron-withdrawing group. When M is Ga or Fe, then m is 0 and n is 3.
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Paragraph 0052; 0057
(2017/01/23)
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- Compositions for Treatment of Cystic Fibrosis and Other Chronic Diseases
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The present invention relates to pharmaceutical compositions comprising an inhibitor of epithelial sodium channel activity in combination with at least one ABC Transporter modulator compound of Formula A, Formula B, Formula C, or Formula D. The invention also relates to pharmaceutical formulations thereof, and to methods of using such compositions in the treatment of CFTR mediated diseases, particularly cystic fibrosis using the pharmaceutical combination compositions.
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- Discovery of N -(2,4-Di- tert -butyl-5-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide (VX-770, Ivacaftor), a potent and orally bioavailable CFTR potentiator
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Quinolinone-3-carboxamide 1, a novel CFTR potentiator, was discovered using high-throughput screening in NIH-3T3 cells expressing the F508del-CFTR mutation. Extensive medicinal chemistry and iterative structure-activity relationship (SAR) studies to evaluate potency, selectivity, and pharmacokinetic properties resulted in the identification of N-(2,4-di-tert-butyl-5-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide (VX-770, 48, ivacaftor), an investigational drug candidate approved by the FDA for the treatment of CF patients 6 years of age and older carrying the G551D mutation.
- Hadida, Sabine,Van Goor, Fredrick,Zhou, Jinglan,Arumugam, Vijayalaksmi,McCartney, Jason,Hazlewood, Anna,Decker, Caroline,Negulescu, Paul,Grootenhuis, Peter D. J.
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p. 9776 - 9795
(2015/01/16)
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- METALLOCENE COMPLEX AND METHOD FOR POLYMERIZING OLEFIN
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A metallocene complex by which high uptake efficiency of ethylene and/or α-olefin can be obtained compared with the conventional metallocene catalyst, and rubber component having high molecular weight can be polymerized, and polymerization method of olefi
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Paragraph 0183-0184
(2013/03/26)
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- PROCESS FOR THE PREPARATION OF M-SUBSTITUTED ALKYLTOLUENES BY ISOMERIZATION WITH IONIC LIQUIDS AS CATALYSTS
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The invention relates to a process for the preparation of m-substituted alkyltoluenes of the formula (I) in which R1 is C1-C5-alkyl, wherein a p-substituted alkyltoluene of the formula (II) in which R1 has the meaning given under formula (I), is isomerized in the presence of ionic liquids to give an m-substituted alkyltoluene of the formula (I). The m-substituted alkyltoluenes obtainable according to the invention are starting compounds for the preparation of fragrances and aroma substances.
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Page/Page column 3
(2011/08/22)
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- COMPOSITIONS FOR TREATMENT OF CYSTIC FIBROSIS AND OTHER CHRONIC DISEASES
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The present invention relates to pharmaceutical compositions comprising an inhibitor of epithelial sodium channel activity in combination with at least one ABC Transporter modulator compound of Formula A, Formula B, Formula C, or Formula D. The invention also relates to pharmaceutical formulations thereof, and to methods of using such compositions in the treatment of CFTR mediated diseases, particularly cystic fibrosis using the pharmaceutical combination compositions.
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- Propanal Production Methods
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A product of p-tert-butylphenyl propionaldehyde and m-tert-butylphenyl propionaldehyde, wherein m-tert-butylphenyl propionaldehyde is in an amount from 6% to 60% of the combination of p-tert-butylphenyl propionaldehyde and m-tert-butylphenyl propionaldehyde. Also a method including; adding dropwise an aldehyde solution to a basic solution; and, collecting a fraction of p-tert-butyl cinnamic aldehyde m-tert-butyl cinnamic aldehyde therefrom; and, adding a transition metal catalyst to a solution of the p-tert-butyl cinnamic aldehyde in ethanol, and, collecting therefrom by distillation a product of p-tert-butylphenyl propionaldehyde and the meta isomer m-tert-butylphenyl propionaldehyde; wherein the product comprises m-tert-butylphenyl propionaldehyde in an amount from 6% to 60% of the combination of p-tert-butylphenyl propionaldehyde and m-tert-butylphenyl propionaldehyde.
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Page/Page column 3
(2010/10/19)
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- Expected and unexpected photochemical reactions of acyl iodides
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Photolysis of acyl iodides RCOI (R = Me, Me2CH, Ph) under UV irradiation in toluene environment for 20-55 h proved to be a simple and efficient method of preparation of symmetrical α-diketones RCOCOR. In contrast, the photolysis under the same
- Voronkov,Vlasova,Vlasov,Belousova,Grigor'Eva,Albanov,Myachina,Vakul'Skaya
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experimental part
p. 1616 - 1620
(2010/04/27)
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- Interconversion equilibria between tert-butylbenzenes and tert-butyltoluenes
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The equilibrium of six positional isomerization reactions in the systems of sterically unhindered tert-butylbenzenes (TBB) and tert-butyltoluenes (TBT) was experimentally studied in the liquid phase over a wide temperature range. The thermodynamic charact
- Nesterov,Nesterova,Vodenkova,Naumkin,Repkin
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experimental part
p. 193 - 200
(2010/04/05)
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- Modulators of ATP-binding cassette transporters
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Compounds of the present invention and pharmaceutically acceptable compositions thereof, are useful as modulators of ATP-Binding Cassette (“ABC”) transporters or fragments thereof, including Cystic Fibrosis Transmembrane Conductance Regulator (“CFTR”). The present invention also relates to methods of treating ABC transporter mediated diseases using compounds of the present invention.
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Page/Page column 150
(2008/06/13)
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- Determination of critical temperatures for mixtures of alkylbenzenes
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The liquid-vapor critical temperatures of benzene mixtures with 1,3-di-tert-butylbenzene, 1,4-di-tert-butylbenzene, and 1,3,5-tri-tert- butylbenzene; a mixture of di-tert-butylbenzene isomers; and a toluene mixture with 3,5-di-tert-butyltoluene were determined over the entire range of composition by means of the amouule method. It was found that the excess critical temperature of the mixtures is related to the critical volumes of the substances. The capabilities of several calculation methods for predicting the critical temperature of mixtures were analyzed on the basis of published data and the obtained results. The Lee-Kesler rules of mixtures were refined by introducing binary interaction parameters.
- Nesterov,Nazmutdinov,Sarkisova,Nesterova,Vodenkova
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p. 434 - 441
(2008/09/16)
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- Alkylation on graphite in the absence of Lewis acids
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Graphite is introduced as a convenient catalyst for alkylation of aromatic compounds and alcohols by benzyl, tertiary alkyl, and secondary alkyl halides in the absence of strong Lewis acids. Primary alkyl halides are not active under the reaction conditions.
- Sereda, Grigoriy A.
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p. 7265 - 7267
(2007/10/03)
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- OPIOID RECEPTOR ACTIVE COMPOUNDS
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The invention provides compounds of formula I: wherein R1 to R4 and n have any of the meanings defined in the specification and their pharmaceutically acceptable salts. The invention also provides pharmaceutical compositions comprising a compound of formula I, processes for preparing compounds of formula I, intermediates useful for preparing compounds of formula I, and therapeutic methods for treating pain and treating other conditions which involve, for example, binding opioid receptors using compounds of formula I.
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- Detailed Characterization of p-Toluenesulfonic Acid Monohydrate as a Convenient, Recoverable, Safe, and Selective Catalyst for Alkylation of the Aromatic Nucleus
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Alkylation of the aromatic nucleus, an important reaction in industry and synthetic organic chemistry, has traditionally been carried out by the well-known Friedel-Crafts reaction employing Lewis acid catalysts such as AlCl3 and BF3 or by using highly reactive organometallic reagents. Although protic acids such as anhydrous HF and concentrated H2SO4 have also been used in the alkylation of the aromatic nucleus, the notoriously corrosive, highly toxic, and hazardous nature of these agents has precluded their common use under ordinary laboratory conditions. Various organic sulfonic acids have, on occasion, been used as catalysts in Friedel-Crafts alkylations, but to our knowledge the chemistry and the scope of these reactions for common laboratory use have never been exploited in detail. In the present study we have characterized commercially available p-toluenesulfonic acid monohydrate (TsOH) as an efficient catalyst for the intermolecular coupling of the aromatic nucleus with activated alkyl halides, alkenes, or tosylates under mild conditions in an open atmosphere. In comparison to conventional Friedel-Crafts catalysts such as AlCl3, BF3, HF, and concentrated H2SO4, the extent of the formation of undesired products from side reactions such as transalkylation, polymerization, etc. was minimal with the TsOH-catalyzed reaction. The ability to recover and reuse the catalyst from the reaction mixtures, minimal generation of environmentally unfriendly waste, high specificity of the reaction, and the low cost of the catalyst are important advantages of the TsOH catalyst over the other conventional Friedel-Crafts catalysts.
- Mahindaratne, Mathew P. D.,Wimalasena, Kandatege
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p. 2858 - 2866
(2007/10/03)
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- NEW WAYS OF GENERATING ORGANOTIN REACTIVE INTERMEDIATES FOR ORGANIC SYSNTHESIS
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Progress in generating and applying two important organotin reactive species for organic synthesis is reported. - Stannyl radicals R3Sn., at present the most used tools for free radical synthesis of complicated target molecules, are generally obtained from the hydrides R3SnH.In a number of cases, however, this is a drawback because of the high radical scavenging power of the latter.New ways of generating R3Sn., decoupling them from the presence of R3SnH, are developed and discussed: the spontaneous thermal dissociation of distannanes with bulky substituents, the thermal fragmentation of bistannyl benzpinacols, the ketone sensitized mild photolysis of simple distannanes, and the mild photolysis of benzyltin compounds such as 9-stannyl-9,10-dihydro anthracene.Examples of advantageous applications, also in combinations with adjusted H donors, are given. - Stannyl cations R3Sn(+) are used as superior leaving groups in electrophilic aromatic ipso substitution.Examples for their application under very mild conditions include the considerable broadening of the scope of the Friedel-Crafts acylation, the Vilsmeier formylation, sulfinations, and sulfonations.The directing influence of certain other substituents can be overcome by this ipso substitution.
- Neumann, Wilhelm P.,Hillgaertner, Horst,Baines, Kim M.,Dicke, Rita,Vorspohl, Klaus,et al.
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p. 951 - 960
(2007/10/02)
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- BORON, ALUMINUM, AND GALLIUM TRIS(TRIFLUOROMETHANESULFONATE) (TRIFLATE): EFFECTIVE NEW FRIEDEL-CRAFTS CATALYSTS.
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Boron, aluminum, and gallium tris(trifluoromethanesulfonate) (triflate) were prepared from the corresponding chlorides (bromides) and triflic acid. The group IIIA triflates were isolated in pure form and fully characterized (elemental analysis, molecular weight, and NMR and IR spectroscopy). Boron tris(triflate) is a monomeric, relatively volatile compound left bracket mp 43-45 degree C, bp 68-73 degree C (0. 5 Torr) right bracket , whereas aluminum and gallium triflate are associated, high-melting associated solids. Boron, aluminum, and gallium tris(triflate) are efficient new Friedel-Crafts catalysts as shown in alkylation, isomerization, and acylation reactions. Alkylation of benzene and toluene with methyl, ethyl, isopropyl, and tert-butyl halides (fluoride, chloride, and bromide) were carried out with boron, aluminum, and gallium tris(triflate) as catalyst in CH//2Cl//2 and CH//3NO//2 solvent at room temperature.
- Olah,Farooq,Morteza,Farnia,Olah
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p. 2560 - 2565
(2007/10/02)
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- A comparative study of gas phase aromatic desilylation and detertbutylation by charged electrophiles
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Aromatic desilylation and detertbutylation by CH5+, C2H5+, i-C3H7+, and t-C4H9+ ions have been studied in the gas phase by mass spectrometric and radiolytic techniques.The higher rate of desilylation than of dealkylation in traced to the step involving the formation of ipso arenium ions, protonated at the ring carbon bearing the SiMe3 or the CMe3 substituent.The latter has been shown by ab initio calculations at the SCFSTO-3G level to selectively depress the basicity of the ipso position, hence the stability of the corresponding arenium ion relative to its protomers, e.g. the basicity of the ipso position of PhCMe3 is lower by ca. 11 kcal mol-1 than of the para position.The SiMe3 group has no comparable effect, very close basicities being computed for the para and the ipso position of PhSiMe3.The different effects of the CMe3 and SiMe3 groups are traced to electronic and steric factors.
- Cacace, Fulvio,Crestoni, M. Elisa,Petris, Giulia De,Fornarini, Simonetta,Grandinetti, Felice
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p. 3099 - 3107
(2007/10/02)
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- ARYLALKYLATION OF 4-tert-BUTYLTOLUENE WITH SUBSTITUTED BENZYL CHLORIDES
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The reaction of 4-alkylbenzyl chlorides with 4-tert-butyltoluene in the presence of titanium tetrachloride and ferric chloride leads to the formation of 2-methyl-4'-alkyl-5-tert-butyldiphenylmethanes.The arylalkylation of 4-tert-butyltoluene with 2- and 4-chlorobenzyl chlorides, catalyzed by titanium tetrachloride, leads to the formation of mixtures of 2-methyl-5-tert-butyldiphenylmethane, 2-tert-butyl-5-methyldiphenylmethane, and isomeric methyldiphenylmethanes containing a chloride atom in the benzyl fragment.The products of the reaction catalyzed by ferric chloride do not contain 2-tert-butyl-5-methylchlorodiphenylmethanes.The reacti on of 4-nitrobenzyl chloride with 4-tert-butyltoluene in the presence of ferric chloride leads to the formation of a mixture of 2-methyl-4'-nitro-5-tert-butyldiphenylmethane and isomeric methylnitrodiphenylmethanes.Under the influence of AlCl3-CH3NO2 in benzene 2,4'-dimethyl-5-tert-butyldiphenylmethane eliminates both the 4-methylbenzyl group and the tert-butyl group.Under analogous conditions 2-methyl-5-tert-butyldiphenylmethanes containing a chlorine atom or a nitro group in the benzyl fragment are dealkylated with the elimination of only the tert-butyl group.
- Pozdnyakovich, Yu. V.,Savyak, R. P.,Shein, S. M.
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p. 522 - 526
(2007/10/02)
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- FRIEDEL-CRAFTS ALKYLATION OF ANISOLE AND ITS COMPARISON WITH TOLUENE. PREDOMINANT ORTHO-PARA SUBSTITUTION UNDER KINETIC CONDITIONS AND THE EFFECT OF THERMODYNAMIC ISOMERIZATIONS
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The AlCl3 and BF3, as well as 65percent HPF6, catalyzed Friedel-Crafts alkylation of anisole with alkyl halides and alkohols was investigated.The alkylation of anisole with lower catalyst concentrations under mild conditions shows predominant ortho/para directing effect generally with a ratio of c.a. 2:1, with the amount of meta isomer uniformly less than 3percent.With "swamping" catalyst conditions the amount of meta substitution in methylation and ethylation can substantially increase.The isomer distribution in tert-butylation changes with time due to rapid ortho-para interconversion.Consequently, the AlCl3-catalyzed isomerization of isomeric alkylanisoles was also studied.In case of tert-butylanisoles, the ortho isomer shows relatively rapid conversion into para followed by much slower isomerization to meta.The para and meta isomers show isomerization to meta-para mixtures.Isomerization of ethyl-, isopropyl-, and benzylanisoles is generally slow whereas methylanisoles do not isomerize.Comparing results of the alkylation of anisole with toluene leads to the conclusion that the latter are readily affected by concurrent (and in some cases consecutive) isomerization.As the barrier for isomerization in the benzenium ion intermediates of the alkylations is higher in the case of CH3O- than CH3-substituted systems, anisole tends to give the kinetically controlled ortho-para alkylation products and the amount of meta isomer is low.Study of alkylation of 3,5-di- and 2,4,6-trideuterated toluene and anisole and comparing retained deuterium contents with isomer distributions shows that alkylated product formation in case of toluene, but not of anisole, is proceeded by intramolecular, 1,2-alkyl, and hydrogen-deuterium shifting resulting also in increased meta substitution.This effect is most predominant in methylation and ethylation where the alkyl shifts are intramolecular but not in tert-butylation and benzylation, where alkyl transfer is intermolecular.Isopropylation is intermediate in nature.No simple selectivity-reactivity relationship is indicated in the studied alkylation reactions.As shown in benzylations with increasingly electron-donating and -withdrawing substituted benzyl chlorides overall rate (i.e., substrate selectivity) and isomer distributions (i.e., regioselectivity) are not determined in the same step as significantly decreased substrate selectivity is not accompanied by loss of positional selectivity.Previously reported alkylations showing high degree of meta substitution therefore, must have been affected by thermodynamically controlled rearrangement processes, including intramolecular alkyl and hydrogen shifts in the arenium ion intermediates of the alkylation reactions.These are to be differentiated from possible subsequent product isomerizations.Under predominantly kinetic conditions anisole as well as toluene are substantially ortho-para directing in alkylations, as in other electrophilic aromatic substitutions.
- Olah, George A.,Olah, Judith A.,Ohyama, Toshiyuki
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p. 5284 - 5290
(2007/10/02)
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- Alkylation of Nitriles with Gaseous Carbenium Ions. The Ritter Reaction in the Dilute Gas State
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Radiolytically formed carbenium ions, such as sec-C3H7+, sec-C4H9+, and t-C4H9+, react in the gas phase with model aliphatic and aromatic nitriles yielding the corresponding nitrilium ions.The latter undergo efficient condensation with water that eventually leads to the formation of the corresponding N-alkylamides.The mechanism is analogous to the Ritter reaction in solution.The reactivity and selectivity of the gas-phase electrophilic attack on nitriles has been deduced from competition experiments under conditions that largely exclude the effects of solvation, ion pairing, etc., which complicate the interpretation of solution-chemistry measurements.
- Cacace, Fulvio,Ciranni, Giovanna,Giacomello, Pierluigi
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p. 2258 - 2261
(2007/10/02)
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- Efficient Coupling of Tertiary Alkyl Halides with Dialkylzinc and Titanium Compounds
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Dialkylzinc compounds react with tertiary halides to afford the corresponding coupling products containing a quaternary carbon atom, thereby making geminal dialkylation of ketones or hydroalkylation of olefins possible.
- Reetz, Manfred T.,Wenderoth, Bernd,Peter, Roland,Steinbach, Rainer,Westermann, Juergen
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p. 1202 - 1204
(2007/10/02)
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