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固定化脂肪酶催化菜籽油合成蜡酯 被引量:10
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作者 赵晶晶 邓利 +1 位作者 谭天伟 王芳 《化工进展》 EI CAS CSCD 北大核心 2007年第9期1311-1315,共5页
以菜籽油、鲸蜡醇为原料,采用实验室自制的固定化Candidia sp.99-125脂肪酶分别在有机溶剂和无溶剂体系下合成了蜡酯,在两种体系下对影响蜡酯合成的各种因素进行了比较研究,研究表明:以正己烷为反应介质,在40℃条件下反应12h,油醇摩尔比... 以菜籽油、鲸蜡醇为原料,采用实验室自制的固定化Candidia sp.99-125脂肪酶分别在有机溶剂和无溶剂体系下合成了蜡酯,在两种体系下对影响蜡酯合成的各种因素进行了比较研究,研究表明:以正己烷为反应介质,在40℃条件下反应12h,油醇摩尔比1∶2,酶量15%(质量分数,上同),水含量7.5%,蜡酯产率可达85.87%;无溶剂体系中在50℃条件下反应20h,油醇摩尔比1∶1.5,蜡酯产率可达80.68%。通过流加鲸蜡醇可以提高酶的使用寿命。 展开更多
关键词 蜡酯 脂肪酶 转酯化 正己烷 无溶剂
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Solvent-free alkylation of dimethyl malonate using benzyl alcohols catalyzed by FeCl_3/SiO_2 被引量:1
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作者 Mohammad Reza Shushizadeh Masumeh Kiany 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1068-1072,共5页
Activated methylene compound such as dimethyl malonate reacted readily with benzylic alcohols in the presence of ferric chloride/silica gel mixture (FeCl3/SiO2) under microwave irradiation to produce benzylic deriva... Activated methylene compound such as dimethyl malonate reacted readily with benzylic alcohols in the presence of ferric chloride/silica gel mixture (FeCl3/SiO2) under microwave irradiation to produce benzylic derivative of dimethyl malonate in high yields in solvent-free condition. 2009 Mohammad Reza Shushizadeh. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 solvent-flee ALKYLATION Activated methylene compounds Benzyl alcohols Microwave irradiation
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无溶剂体系中毕赤酵母表面展示CALB全细胞催化合成肉桂醇酯 被引量:1
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作者 徐晓敏 黄奎 韩双艳 《现代食品科技》 EI CAS 北大核心 2018年第5期101-107,共7页
利用表面展示南极假丝酵母脂肪酶B(Candida antarctica lipase B,CALB)的毕赤酵母细胞(Pp-CALB)为全细胞催化剂,以不同脂肪酸作为酰基供体,在无溶剂体系中和肉桂醇发生酯化反应合成肉桂醇酯。探究了Pp-CALB对于不同酰基供体的选择性,并... 利用表面展示南极假丝酵母脂肪酶B(Candida antarctica lipase B,CALB)的毕赤酵母细胞(Pp-CALB)为全细胞催化剂,以不同脂肪酸作为酰基供体,在无溶剂体系中和肉桂醇发生酯化反应合成肉桂醇酯。探究了Pp-CALB对于不同酰基供体的选择性,并且对反应温度、摇床转速、酶加量、底物摩尔比、酶的水活度和反应体系等一系列影响酶催化反应的因素进行了优化,建立了无溶剂体系中肉桂醇酯的酶法合成工艺。结果表明,在底物摩尔比为2:1,摇床转速为120 r/min,反应温度为50℃的条件下,添加初始水活度为0.53的Pp-CALB 0.05 g,反应3h,肉桂醇的酯化率可达81.34%,在最适反应条件下,使用Pp-CALB连续反应8次后,肉桂醇的酯化率仍然能达到70.00%以上,具有较好的操作稳定性。 展开更多
关键词 酵母表面展示 南极假丝酵母脂肪酶B 全细胞催化剂 无溶剂 肉桂醇酯
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Silica Gel-Supported Polyphosphoric Acid (PPA/SiO2): An Efficient and Reusable Heterogeneous Catalyst for Facile Synthesis of 14-Aryl-14H-dibenzo[aj]xanthenes under Solvent-free Conditions 被引量:8
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作者 Khojastehnezhad Amir Davoodnia Abolghasem Bakavoli Mehdi Tavakoli-Hoseini Niloofar Zeinali-Dastmalbaf Mohsen 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第2期297-302,共6页
A simple, efficient and green method for the synthesis of 14-aryl-14H-dibenzo[aj]xanthenes by a one-pot condensation reaction of β-naphthol and aryl aldehydes using silica gel-supported polyphosphoric acid (PPA/SiO2... A simple, efficient and green method for the synthesis of 14-aryl-14H-dibenzo[aj]xanthenes by a one-pot condensation reaction of β-naphthol and aryl aldehydes using silica gel-supported polyphosphoric acid (PPA/SiO2), an effective and reusable catalyst, under solvent-free conditions is described. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents. 展开更多
关键词 14-Aryl-14H-dibenzo[a j]xanthenes PPA/SiO2 heterogeneous catalysis green chemistry solvent-flee conditions
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Synthesis of Some New 1,4-Dihydropyridine Derivatives through a Facile One-pot Hantzsch Condensation Catalyzed by Triethylamine 被引量:1
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作者 Ghalem, Wassima Boulcina, Raouf Debache, Abdelmadjid 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第3期733-737,共5页
A facile and efficient synthesis of new 1,4-dihydropyridine derivatives was reported via Hantzsch three-com- ponent condensation reaction of aldehydes or formylphenylboronic acids, ethyl acetoacetate, and ammonium ace... A facile and efficient synthesis of new 1,4-dihydropyridine derivatives was reported via Hantzsch three-com- ponent condensation reaction of aldehydes or formylphenylboronic acids, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of triethylamine under solvent-free conditions. The method described here of- fers several advantages including high yields, short reaction times, and simple work-up procedure. 展开更多
关键词 1 4-DIHYDROPYRIDINE TRIETHYLAMINE formylphenylboronic acid Hantzsch reaction solvent-flee condi-tion
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Esterification of Carboxylic Acids and Diacids by Trialkyl Borate under Solvent- and Catalyst-Free Conditions 被引量:1
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作者 MANSOORI, Yagoub TATAROGLU SEYIDOV, Firdovsi +2 位作者 BOHLOOLI, Shahrbanoo ZAMANLOO, Mohammad Reza IMANZADEH, Gholam Hassan 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第12期1878-1882,共5页
Esterification or transesterification reactions are usually carried out in the presence of homogeneous or heterogeneous catalysts. However, recently a new method was reported for the esterification of carboxylic acids... Esterification or transesterification reactions are usually carried out in the presence of homogeneous or heterogeneous catalysts. However, recently a new method was reported for the esterification of carboxylic acids by tributyl borate under solvent- and catalyst-free conditions. In order to show the synthetic ability of trialkyl borate esters in the esterification reactions, here, the esterification of other carboxylic acids and diacids by tributyl-, triisoamyl-, and tribenzyl borate under the same conditions were reported. Some of the prepared ester and diester products have found wide applications as plasticizers and synthetic ester base lubricants. The esterification reactions have been cleanly carried out in the absence of any solvent under catalyst-free conditions. The maximum rate belongs to isoamyl trichloroacetate (VIb) which reached about 76% within about 6.5 h. On the basis of obtained findings, it seems that electron withdrawing groups on carboxylic acid facilitate the esterification reaction. 展开更多
关键词 ESTERIFICATION borate ester solvent-flee
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