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Catalytic synthesis of cyclohexanone 1,2-propanediol ketal with H_4SiW_(12)O_(40)/PAn 被引量:13
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作者 YANGShuijin YUXieqing SUNJutang 《Rare Metals》 SCIE EI CAS CSCD 2004年第4期300-305,共6页
A new environmental friendly catalyst, H_4SiW_(12)O_(40)/PAn was prepared andidentified by means of FT-IR, XRD and TG/DTA. Cyclohexanone 1,2-propanediol ketal was synthesizedfrom cyclohexanone and 1,2-propanediol in t... A new environmental friendly catalyst, H_4SiW_(12)O_(40)/PAn was prepared andidentified by means of FT-IR, XRD and TG/DTA. Cyclohexanone 1,2-propanediol ketal was synthesizedfrom cyclohexanone and 1,2-propanediol in the presence of H_4SiW_(12)O_(40)/PAn The factorsinfluencing tlie synthesis were discussed and the best conditions were found out. The optimumconditions are: molar ratio of cyclohexanone to 1,2-propanediol is 1:1.4, the quantity of catalystis equal to 1.0 percent of feed stocks, and the reaction time is 40 min. H_4SiW_(12)O_(40)/PAn is anexcellent catalyst for synthesizing cyclohexanone 1,2-propanediol ketal and its yield can reachover 96.5 percent. 展开更多
关键词 cyclohexanone 1 2-propanediol ketal 12-Tungstosilicic acid POLYANILINE CATALYST ketalATION
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Solventless ketalization of glycerol to solketal with acetone over the ionic liquid[P(C4H9)3C14H29][TsO]
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作者 Yu Ji Tengda Zhang +2 位作者 Xia Gui Haijian Shi Zhi Yun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期158-164,共7页
The ketalization of glycerol with acetone was conducted over an ionic liquid[P(C4H9)3C14H29][TsO](TTPT)in a batch reactor.A scheme to obtain the purified product using TTPT as a homogeneous catalyst is proposed and a ... The ketalization of glycerol with acetone was conducted over an ionic liquid[P(C4H9)3C14H29][TsO](TTPT)in a batch reactor.A scheme to obtain the purified product using TTPT as a homogeneous catalyst is proposed and a maximum solketal yield of 86%is achieved at acetone/glycerol molar ratio of 6/1,reaction time of 0.5 h,reaction temperature of 303 K,catalyst amount of 5 wt%of glycerol.TTPT was recycled and reused for ten times without obvious losses in terms of quantity and activity.Furthermore,effects of various experimental parameters(stirring speed,catalyst loadings,temperature and reactant composition)on the reaction kinetics are investigated.In terms of kinetics modeling,Kγis fitted by reactant composition at the temperature range 298 K–323 K,which was a concise strategy that showed good precision in the kinetics fitting.The activation energy for this ketalization reaction was evaluated to be 28.2 kJ·mol^-1.In addition,the kinetics of the reaction at a temperature exceeding the boiling point of acetone were also studied.We believe that all the results are important for further development of a technology for the continuous synthesis of solketal. 展开更多
关键词 Ionic liquid ketalIZATION Solketal GLYCEROL Reaction kinetics Reactive DISTILLATION
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A validated, related substance, GC method for 1,4-cyclohexanedione mono-ethylene Ketal
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作者 B. Karthikeyan V. Srinivasan 《Journal of Biophysical Chemistry》 2010年第1期72-75,共4页
ABSTRACT A simple, economic, and time-efficient related substance, GC method has been developed for the analysis of 1,4-Cyclohexanedione mono- ethylene ketal(will be specified as ketal) in the presence of a potential ... ABSTRACT A simple, economic, and time-efficient related substance, GC method has been developed for the analysis of 1,4-Cyclohexanedione mono- ethylene ketal(will be specified as ketal) in the presence of a potential impurity 1,4-cyclohexa- nedione bis (ethylene ketal) [will be specified as diketal]. Successful chromatographic separa- tion of the ketal from the impurity was achieved on a DBWAX ETR, 30 m x 0.32 mm x 1.0μ FT column with nitrogen as carrier gas and FID detector. The method was validated for linearity, accuracy, precision, and specificity and can be used for quality control during manufacture of ketal. A validated GC method is reported for the ketal for the first time. 展开更多
关键词 Column Gas CHROMATOGRAPHY 1 4-Cyclohexanedione Mono-Ethylene ketal 4-Cyclohexanedione BIS (Ethylene ketal) Validation
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Catalytic synthesis of acetals and ketals with H3PW12O40/PAn 被引量:11
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作者 YANG Shuijin ZHANG Yijun +1 位作者 DU Xinxian Philippe G. Merle 《Rare Metals》 SCIE EI CAS CSCD 2008年第1期89-94,共6页
A new environmental friendly catalyst H3PW12O40/PAn was prepared and identified by means of FT-IR,XRD,and TG/DTA.The optimum conditions have been found;that is,the mass ratio of PAn to H3PW12O40 is 1:1.5,the volume o... A new environmental friendly catalyst H3PW12O40/PAn was prepared and identified by means of FT-IR,XRD,and TG/DTA.The optimum conditions have been found;that is,the mass ratio of PAn to H3PW12O40 is 1:1.5,the volume of methanol is 20 mL,and the reflux reaction time is 3 h.The structural identity of Keggin units is preserved after the incorporation into polyaniline matrix.Catalytic activities of H3PW12O40/PAn in synthesizing 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,cyclohexanone ethylene ketal,cyclohexanone 1,2-propanediol ketal,butanone ethylene ketal,butanone 1,2-propanediol ketal,2-phenyl-1,3-dioxolane,4-methyl-2-phenyl-1,3-dioxolane,2-propyl-1,3-dioxolane,and 4-methyl-2-propyl-1,3-dioxolane were reported.It has been demon-strated that H3PW12O40/PAn is an excellent catalyst.Various factors concerned in these reactions were investigated.The optimum conditions are as follows:the molar ratio of aldehyde/ketone to glycol(r) is 1:1.5,the mass ratio of the catalyst used to the reactants is 0.6%,and the reaction time is 1.0 h.Under these conditions,the yield is as follows:2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,69.0%;2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,79.5%;cyclohexanone ethylene ketal,78.9%;cyclohexanone 1,2-propanediol ketal,85.3%;butanone ethylene ketal,56.9%;butanone 1,2-propanediol ketal,78.1%;2-phenyl-1,3-dioxolane,76.3%;4-methyl-2-phenyl-1,3-dioxolane,94.2%;2-propyl-1,3-dioxolane,70.7%;and 4-methyl-2-propyl-1,3-dioxolane,79.2%. 展开更多
关键词 phosphotungstic acid ACETAL ketal POLYANILINE CATALYSIS
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Tungstophosphoric heteropolyacid supported onto neutral alumina: characterization and synthesis of acetals and ketals 被引量:6
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作者 GAO Jinzhang WEI Yunxia WANG Xuemei YANG Wu 《Rare Metals》 SCIE EI CAS CSCD 2007年第2期152-157,共6页
Tungstophosphoric acid (HPW) catalyst supported on the neural alumina was studied. It was prepared by means of an equilibrium and incipient wetness impregnation technique. Solution of HPW in 50% V/V ethanol-water wa... Tungstophosphoric acid (HPW) catalyst supported on the neural alumina was studied. It was prepared by means of an equilibrium and incipient wetness impregnation technique. Solution of HPW in 50% V/V ethanol-water was used to impregnate Al2O3 at 25℃. It was found that the catalyst containing 30% PW by calcination at 500℃ showed a higher catalytic activity in the synthesis of acetals and/or ketals. In the following condition, that is, the molar ratio of aldehyde/ketone to glycol being 1:1.5, the mass fraction of the catalyst used was 0.5%, and the reaction time was 1.0 h; the yields of ketals and acetals could reach up to 60.5%-86.7%. Moreover, it could be easily recovered and reused. 展开更多
关键词 HETEROPOLYACID tungstophosphodc catalyst catalytic activity ACETAL ketal.
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Synthesis of acetals and ketals catalyzed by tungstosilicic acid supported on active carbon 被引量:9
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作者 杨水金 杜心贤 +1 位作者 贺兰 孙聚堂 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第5期373-377,共5页
Catalytic activity of activated carbon supported tungstosilicic acidin synthesizing 2-methyl-2-ethoxycarbonylmethyl- 1,3-dioxolane, 2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane, cyclohexanone ethylene ketal, cycl... Catalytic activity of activated carbon supported tungstosilicic acidin synthesizing 2-methyl-2-ethoxycarbonylmethyl- 1,3-dioxolane, 2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane, cyclohexanone ethylene ketal, cyclohexanone 1,2-propa- nediol ketal, butanone ethylene ketal, butanone 1,2-propanediol ketal, 2-phenyl-1,3-dioxolane, 4-methyl-2-phenyl-1,3-dioxolane, 2-propyl-1,3-dioxolane, 4-methyl-2-propyl-1,3-dioxolane was reported. It has been demonstrated that activated carbon supported tungstosilicic acid is an excellent catalyst. Various factors involved in these reactions were investigated. The optimum conditions found were: molar ratio of aldehyde/ketone to glycol is 1/1.5, mass ratio of the catalyst used to the reactants is 1.0%, and reaction time is 1.0 h. Under these conditions, the yield of 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane is 61.5%, of 2,4-dimethyl- 2-ethoxycarbonylmethyl-1,3-dioxolane is 69.1%, of cyclohexanone ethylene ketal is 74.6%, of cyclohexanone 1,2-propanediol ketal is 80.1%, of butanone ethylene ketal is 69.5%, of butanone 1,2-propanediol ketal is 78.5%, of 2-phenyl-1,3-dioxolane is 56.7%, of 4-methyl-2-phenyl-1,3-dioxolane is 86.2%, of 2-propyl-1,3-dioxolane is 87.5%, of 4-methyl-2-propyl-1,3-dioxolane is 87.9%. 展开更多
关键词 Tungstosilicic acid Aceta ketal Active carbon CATALYSIS
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Eco-friendly one-pot synthesis of acetals and ketals by heterogeneously catalyzed liquid-solid phase reaction 被引量:5
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作者 YANG Shuijin WANG Min +1 位作者 LIANG Yongguang SUN Jutang 《Rare Metals》 SCIE EI CAS CSCD 2006年第6期625-629,共5页
Twelve classes of acetals and ketals were synthesized from aldehyde/ketone and glycol using ZiSiW12O40/TiO2 as a novel eco-friendly catalyst. The physical characterizations were carried out by TG/DTA, FT-IR, XRD, and ... Twelve classes of acetals and ketals were synthesized from aldehyde/ketone and glycol using ZiSiW12O40/TiO2 as a novel eco-friendly catalyst. The physical characterizations were carried out by TG/DTA, FT-IR, XRD, and ^1H NMR spectra. The results indicated that the catalyst showed excellent catalytic activity for the condensation reactions. The yield of 12 classes of acetals and ketals reached 56.3%-96.3% under the typical reaction conditions (the molar ratio of aldehyde/ketone and glycol was 1:1.5, the quantity of catalyst was 0.5% of feed stock, the reaction time was 1.0 h, and the reaction temperature was 80-116℃). The catalyst was easily recovered and reused to give almost the same yield of the product as that given by fresh TiSiW12O10/TiO2. 展开更多
关键词 catalysis heteropoly acid ACETALATION ketalATION ZiSiW12O40/TiO2
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Polyaniline Supported 12-Tungstosilicic Acid as the Catalyst for Acetals and Ketals Synthesis 被引量:1
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作者 杨永金 PHILIPPE G Merle 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第3期371-375,共5页
A novel environmental friendly catalyst, H4SiW12O40/PAn was prepared and identified by FT-IR, XRD and TG/DTA. The optimal synthetic protocol was a PAn to H4SiW12O40 mass ratio of 1 : 1, a 20 mL of methanol and a reac... A novel environmental friendly catalyst, H4SiW12O40/PAn was prepared and identified by FT-IR, XRD and TG/DTA. The optimal synthetic protocol was a PAn to H4SiW12O40 mass ratio of 1 : 1, a 20 mL of methanol and a reaction time of 2 h at reflux. It was used in catalytic synthesis of ten important ketals and acetals with a high catalytic activity. With an aldehyde/ketone to glycol molar ratio of 1 : 1.5 and a 1 wt% catalyst loading, the yields of ketals and acetals could reach 60.0%- 93.8 % after 1 h. 展开更多
关键词 12-tungstosilicic acid POLYANILINE ACETAL ketal catalysis
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H4SiW6Mo6O40-Doped Polyaniline-Synthesis, characterization and catalytic properties of acetals and ketals 被引量:2
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作者 YANG Shui-jin DU xin—xian PhilippeG.Merle 《Journal of Chemistry and Chemical Engineering》 2008年第4期35-41,共7页
A new environmental friendly catalyst, HaSiWrMo6O40/PAn was prepared and identified by means of FT-IR, XRD and TG/DTA. The optimum conditions have been found, that was, mass ratio of m(PAn): m(HaSiW6Mo6On.) was 1... A new environmental friendly catalyst, HaSiWrMo6O40/PAn was prepared and identified by means of FT-IR, XRD and TG/DTA. The optimum conditions have been found, that was, mass ratio of m(PAn): m(HaSiW6Mo6On.) was 1:1.25, volume of methanol was 20 mL, and the reflux reaction time was 2h. The structural identity of Keggin units was preserved after the incorporation into polyaniline matrix. H4SiW6Mo6040/PAn was used as catalyst in catalytic synthesis of acetals and ketals. Effects of n(aldehyde(ketone )): n(glycol), catalyst dosage and reaction time on yield were investingated. Optimal conditions were: n(aldehyde(ketone)): n(glycol)=1.0: 1.5; mass fraction of catalyst to reactants, 0.5%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 15 mL. Under these conditions, yields of actels and ketals were 31.9%-91.6%. 展开更多
关键词 2 4-dimethyl-2-ethoxycarbonylmethyl-1 3-dioxo-lane H4SiW6Mo6O4O polyaniline ACETALATION ketalATION catalyst
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Catalytic synthesis of acetals and ketals with H3PW6Mo6O40/TiO2 被引量:1
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作者 YANG Shui-jin TONG Wen-long Philippe G. Merle 《Journal of Chemistry and Chemical Engineering》 2007年第1期8-11,39,共5页
A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m (TiO2): m (H3PW6Mo6O40) is 1:2.0, volume of water is 30 mL, the reflux react... A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m (TiO2): m (H3PW6Mo6O40) is 1:2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn (aldehyde(ketone)): n (glycol), catalyst dosage and reaction time on yield were investigated. Optimal conditions were: n(aldehyde (ketone)): n (glycol)=1.0 : 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0% 展开更多
关键词 H3PW6MO6O40 TiO2 ACETALATION ketalATION CATALYSIS
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Zeolite-Catalyzed Acetalization Ⅰ. Synthesis of Some Acetals and Ketals through Reaction of Carbonyl Compounds with Ethanediol 被引量:2
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作者 Wei JIANG Yan TIAN +1 位作者 Yu Dao MA Qi Long WANG(Department of Chemistry, Shandong University, Jinan 250100)Lei WANG(Department of Pharmacy, Shandong Medical University, Jinan, 250012) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第5期377-380,共4页
The acetalization of a series of carbonyl compounds with ethanediolwas performed over two self-steaxned HY zeolle catalpsts' The acetal and ketaiproducts were obtained with high ytelds Espectw, the HY zeollte with... The acetalization of a series of carbonyl compounds with ethanediolwas performed over two self-steaxned HY zeolle catalpsts' The acetal and ketaiproducts were obtained with high ytelds Espectw, the HY zeollte with highfraxnework Si/A1 ratio was proven to be suitable cataipst for the acetabotion ofunsaturated carbonyl compounds, during which the C =C double bond was notperturbed 展开更多
关键词 Synthesis of Some Acetals and ketals through Reaction of Carbonyl Compounds with Ethanediol
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Acetalation and Ketalation Catalyzed by SO_4^(2-)/TiO_2-MoO_3
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作者 YANG Shui-jin BAI Ai-min DONG Jing-hua SUN Ju-tang 《合成化学》 CAS CSCD 2004年第z1期138-138,共1页
关键词 Acetal ketal SO42-/TiO2-MoO3 catalysis.
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A NEW METHOD FOR AROMATIZAT ION OF Δ^(5(10))-STEROIDAL C_(3)-DIMETHYL KETALS
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作者 Guang Dian HAN Hong Yan WEN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期107-108,共2页
A new method for aromatization of Δ^(5(10))-steroidal C_3-dimethyl ketals with pyridinium hydrobromide perbromide (PHP.Py·HBr·Br_2) to aromatic A ring steroids in high yield (90-95%) is described.
关键词 ION STEROIDAL C3-DIMETHYL ketalS A NEW METHOD FOR AROMATIZAT ION OF PHP
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DEPROTECTION OF ACETALS AND KETALS WITH CpTiCl_3-KI
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作者 Shao Zu WU Ya Lan ZHANG +1 位作者 Tian Hui REN Ning CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期907-910,共4页
When the mixture of CpTiCl_3-KI is used, many acetals and ketals, which are difficuitly deprotected with CpTiCl_3 alone, can be easily converted to the corresponding carbonyl compounds in high yield at 30℃ in Et_2O.
关键词 DEPROTECTION OF ACETALS AND ketalS WITH CpTiCl3-KI CHEN HIGH
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Stable Send-ketals of 3',5'-O-(Tetraisopropyldisiloxane-1,3-diyl)-2'-Ketouridine
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作者 Guo Chen CHI Zhong Biao ZHANG Xiao Hua Xu and Ru Yu CHEN (Insitute of Elemento-Organic Chemistry, State Key Laboratory of Elemento-Organic Chemistry,Nankai University, Tianjin, 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第11期989-992,共4页
A series of stable semi-ketals were obtained via the reactions of 3',5'-O-(tetraisopropyldisiloxane-1,3-diyl)-2'-ketouridine 1 with primary alcohols. In the addition reaction,only a single diastereomer was... A series of stable semi-ketals were obtained via the reactions of 3',5'-O-(tetraisopropyldisiloxane-1,3-diyl)-2'-ketouridine 1 with primary alcohols. In the addition reaction,only a single diastereomer was observed. The configuration of 3b was confirmed by X-raydiffraction. 展开更多
关键词 NUCLEOSIDE ketonucleoside semi-ketal configuration
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SYNTHESIS OF A KETAL BY USING HPA AS CATALYST
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作者 Wan Sheng YOU Yuan Peng GU +1 位作者 Xiao Hui LIU Xing TIAN (Department of Chemisty, Liaoning Normal University, Dalian, 116022) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第10期821-,222,共2页
The work herein reported is about a rapid and convenient synthetic method of a betal formed from ethylene glycol and cyclohexanone by using H3PW12O40(HPA)as catalyst. It has ben shown that the reaction, by using HPA a... The work herein reported is about a rapid and convenient synthetic method of a betal formed from ethylene glycol and cyclohexanone by using H3PW12O40(HPA)as catalyst. It has ben shown that the reaction, by using HPA as catalyst, can proceed at room temperature and have the high yield of 92% and the catalyst can be used again and again 展开更多
关键词 HPA AS SYNTHESIS OF A ketal BY USING HPA AS CATALYST
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CONVERSION OF ACETALS AND KETALS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl_4-NaBH_4
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作者 Shao Zu WU Hui Dong WANG Ning CHENG Department of Chemistry,Lanzhou University.Lanzhou,730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第1期47-50,共4页
In our study on the chemistry of ZrCl_4-NaBH_4,we have found that aldehydes and ketones can be regenerated from acetals and ketals at 30℃ in Et_2O in high yield The reaction mechanism was discussed.
关键词 MS GC CONVERSION OF ACETALS AND ketalS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl4-NaBH4
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有机催化3-氨基氧化吲哚与偶氮二羧酸酯的不对称加成反应
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作者 张健 田芳 王立新 《合成化学》 CAS 2024年第2期116-123,共8页
手性3,3-双取代氧化吲哚结构单元广泛存在于具有生物活性的天然产物和具有药物活性的化合物中,尤其存在于具有光学活性的3-氨基氧化吲哚中。此外,手性3,3-双取代氧化吲哚结构单元作为有效抗疟药(NITD609)、高效焦虑和抑郁抑制剂(SSR1494... 手性3,3-双取代氧化吲哚结构单元广泛存在于具有生物活性的天然产物和具有药物活性的化合物中,尤其存在于具有光学活性的3-氨基氧化吲哚中。此外,手性3,3-双取代氧化吲哚结构单元作为有效抗疟药(NITD609)、高效焦虑和抑郁抑制剂(SSR149415)以及HIV蛋白酶抑制剂而备受关注。因此,发展合成手性3-氨基氧化吲哚的新方法具有重要意义。为了实现反应的敏感性产物N,N′-缩靛红衍生物的不对称合成,使用金鸡纳碱衍生的方酰胺作催化剂,3-氨基氧化吲哚席夫碱与偶氮二羧酸酯作模板底物,最终以70%~85%的产率和45%~88%的对映选择性获得相应产物。该反应的实验条件温和,原子经济性高。 展开更多
关键词 N N′-缩靛红 不对称催化 3-氨基氧化吲哚席夫碱 偶氮二羧酸酯 亲电加成
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手性磷酸催化非环状N,N′-缩酮的不对称合成
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作者 李敏 李文哲 +1 位作者 黄敏 张晓梅 《合成化学》 CAS 2024年第7期634-642,共9页
手性N,N′-缩酮是药物分子和生物活性化合物最重要的核心结构之一,也是有机合成中重要的催化剂或配体。因此,不对称合成N,N′-缩酮具有重要意义。通过手性磷酸、溶剂、催化剂负载量和投料比的筛选,确定了最佳的反应条件:在手性磷酸的催... 手性N,N′-缩酮是药物分子和生物活性化合物最重要的核心结构之一,也是有机合成中重要的催化剂或配体。因此,不对称合成N,N′-缩酮具有重要意义。通过手性磷酸、溶剂、催化剂负载量和投料比的筛选,确定了最佳的反应条件:在手性磷酸的催化下,以1,4-二氧六环作为溶剂,5-氨基异噁唑与β,γ-炔基-α-酮亚胺酯在室温下发生区域选择性的氮杂-曼尼希反应,实现异噁唑的不对称N—H烷基化,以中等至良好的收率(46%~83% yield)和较好的对映选择性(82%~92%ee)合成非环状的N,N′-缩酮。所有产物结构由^(1)H NMR,^(13)C NMR和HR-MS(ESI)确证,绝对构型通过X-射线晶体结构分析确定。 展开更多
关键词 N N′-缩酮 手性磷酸催化 5-氨基异噁唑 β γ-炔基-α-酮亚胺酯 区域选择性 不对称合成 氮杂-曼尼希反应
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Postsynthesis of hierarchical core/shell ZSM-5 as an efficient catalyst in ketalation and acetalization reactions 被引量:3
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作者 Peng Luo Yejun Guan +2 位作者 Hao Xu Mingyuan He Peng Wu 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2020年第2期258-266,共9页
Hierarchical core/shell Zeolite Socony Mobil-five(ZSM-5)zeolite was hydrothermally postsythesized in the solution of NaOH and diammonium surfactant via a dissolution-reassembly strategy.The silica and alumina species ... Hierarchical core/shell Zeolite Socony Mobil-five(ZSM-5)zeolite was hydrothermally postsythesized in the solution of NaOH and diammonium surfactant via a dissolution-reassembly strategy.The silica and alumina species were firstly dissolved partially from the bulky ZSM-5 crystals and then were reassembled into the MFI-type nanosheets with the structure-directing effect of diammonium surfactant,attaching to the out-surface of ZSM-5 core crystals.The mesopores thus were generated in both the core and shell part,giving rise to a micropore/mesopore composite material.The micropore volume and the acidity of the resultant hybrid were well-preserved during this recrystallization process.Possessing the multiple mesopores and enlarged external surface area,the core/shell ZSM-5 zeolite exhibited higher activity in the ketalation and acetalization reactions involving bulky molecules in comparison to the pristine ZSM-5. 展开更多
关键词 core/shell ZSM-5 in SITU recrystallization MESOPORE ketalATION and ACETALIZATION REACTIONS
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