Polyaniline salts and complexes: Efficient and reusable catalyst for the one‐pot synthesis of 5‐(methoxycarbonyl)‐6‐methyl‐4‐phenyl‐3,4‐dihydropyrimidin‐2(1h)‐one

Polyaniline salts were prepared by doping polyaniline base with different Bronsted acids (sulfuric, nitric, phosphoric, perchloric, hydrochloric acid) and organic acids (p‐toluene sulfonic acid, 5‐sulfosalicylic acid). Polyaniline complexes were also prepared using Lewis acids (aluminum chloride, ferric chloride). Polyaniline salts and polyaniline complexes were used as catalysts in Biginelli reaction for 5‐(methoxycarbonyl)‐6‐methyl‐4‐phenyl‐3,4‐dihydropyrimidin‐2(1H)‐one synthesis. Benzaldehyde and urea were reacted with methyl acetoacetate using polyaniline‐p‐toluene sulfonate salt as catalyst with different reaction time, temperature, and amount of catalyst. The use of polyaniline catalysts is feasible because of the easy preparation, easy handling, stability, easy recovery, simple work‐up procedure, reusability, excellent activity with less amount of catalyst, and eco‐friendly nature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1741–1745, 2006     

Ring‐opening polymerization of caprolactone using novel polyaniline salt catalyst

Hybrid composite of polyaniline metal oxide composite, polyaniline‐dodecyl hydrogen sulfate salt with ferric oxide, was prepared for the first time via simple one‐step process of oxidizing aniline with ferric tris(dodecyl sulfate). Ferric tris(dodecyl sulfate) acts as an oxidant, emulsifier, dopant for polyaniline and also source of ferric oxide. Polyaniline salt composites were prepared via aqueous, emulsion, and interfacial polymerization pathways. Polyaniline salt composite was successfully demonstrated as polymer based solid acid catalysts in the ring‐opening polymerization of ε‐caprolactone for the first time. This methodology gave low molecular weight poly(ε‐caprolactone) (MW‐4035) with highly crystalline polymer of flower petals like morphology in 52 wt% yield (with respect to the amount of ε‐caprolactone used). Advantages of this methodology are the use of easily synthesizable, easily handlable, recyclable, cheaper, and eco‐friendly nature of the catalyst. POLYM. ENG. SCI., 55:2245–2249, 2015. © 2015 Society of Plastics Engineers     

Didecyl ester of 4‐sulfophthalic acid as a plast dopant and emulsifier in the chemical polymerization of aniline into polyaniline salt

Polyaniline salt was synthesized through the chemical oxidation of aniline with sodium persulfate as the oxidant and didecyl ester of 4‐sulfophthalic acid via three different polymerization pathways (aqueous, emulsion, and interfacial). In these polymerization processes, the ester acted as a novel plast dopant and as an emulsifier. The yield, conductivity, and number of ester units present in the polyaniline salts were determined. A polyaniline salt prepared by emulsion polymerization was soluble in chloroform and showed excellent solution‐processing properties. Polyaniline samples prepared by aqueous or interfacial polymerization were not soluble in chloroform. A soluble polyaniline salt was successfully synthesized through the washing of an organic layer containing the polyaniline salt with water in emulsion polymerization. X‐ray diffraction spectra of polyaniline salts prepared by the three different methods showed an ordered, layer‐type supramolecular structure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Polyaniline-supported acid as an efficient and reusable catalyst for a one-pot synthesis of β-acetamido ketones via a four-component condensation reaction

Polyaniline-supported acid salts such as polyaniline-hydrochloride, polyaniline-sulfate and polyaniline-nitrate were prepared by oxidation of aniline using ammonium persulfate as oxidizing agents. Polyaniline salts were used as catalyst for the preparation of β-acetamido ketones. Polyaniline-sulfate salt was found to be the best catalyst for the preparation of β-acetamido ketones. Present methodology offers several advantages, such as cheaper process, easy synthesis of stable catalyst, simple work-up procedure, and excellent activity with less amount of catalyst and in addition, the catalyst can be easily recovered after completion of the reaction and reusable without affecting its activity.     

杂多酸(盐)催化合成肉桂酸异戊酯的研究

以杂多酸（盐）为催化剂,３Ａ分子筛为脱水剂,肉桂酸和异戊醇为原料合成肉桂酸异戊酯,考察了醇酸比、催化剂种类、催化剂用量、反应时间对酯产率的影响。结果表明,在肉桂酸用量为０１ｍｏｌ情况下,用ＡｌＰＷ１２Ｏ４０为催化剂,催化剂用量为１００ｇ,醇酸摩尔比为２５∶１,反应时间３ｈ,反应温度１３５～１４０℃是最适宜的反应条件。酯产率超过９６％。     

无机固体酸催化合成肉桂酸乙酯

在五水四氯化锡存在下，肉桂酸和乙醇发生酯化反应合成肉桂酸乙酯。考察了五水四氯化锡用量、酸醇摩尔比和反应时间对肉桂酸乙酯收率的影响。在n(肉桂酸) ∶n(乙醇)∶n(五水四氯化锡)=1∶7.5∶0.22、回流反应3 h条件下，酯收率达91.4％，并考察了六水三氯化铁、十二水合硫酸铁铵和一水硫酸氢钠催化合成肉桂酸乙酯的催化活性。     

钨锗酸催化合成肉桂酸酯

以钨锗杂多酸为催化剂,对肉桂酸与异戊醇的液相酯化反应进行了研究。考察了催化剂用量、反应时间、醇酸比、带水剂用量等对合成肉桂酸异戊酯的影响,得到合成该酯的较适宜条件。在相近条件下,不同醇的肉桂酸系列酯均可获较理想的酯化率。     

Polyaniline Salts and Complexes as Catalyst in Bisindole Synthesis

Polyaniline salts are prepared by doping of polyaniline base with different Bronsted acids (H₂SO₄, HNO₃ and H₃PO₄), organic acid — p-toluene sulfonic acid (PTSA) and Iodine (I₂). Polyaniline complexes are also prepared using Lewis acids (BF₃, AlCl₃ and SnCl₂). Polyaniline salts and polyaniline complexes are characterized by physical, electrical and spectral methods. Polyaniline salts and polyaniline complexes are used as catalyst for the first time in bisindole synthesis. Bisindole (3,3′-bis(indolyl)phenylmethane) is obtained in excellent yields with simple and more environmental benign procedure. The use of polyaniline catalysts are feasible because of their easy preparation, easy handling, stability, easy recovery, reusability, good activity and eco-friendly.     

Polyaniline salts as polymer‐based solid acid catalyst for low molecular weight poly(lactic acid)

Polymer‐based solid acid catalyst, polyaniline (PANI) salt, is used for the first time to synthesize polymer. In continuation of our work to synthesize organic chemicals using PANI‐based solid acid catalyst, in this work, polylactic acid is synthesized by the condensation polymerization of lactic acid using PANI salts. PANI salts are characterized by FTIR, FE‐SEM, and TGA analyses. Polymerization of lactic acid in xylene solvent at 140°C for 24 h with the use of very low amount of PANI catalysts gave polylactic acid (PLLA) in the order: PANI‐MSA (46%) > PANI‐TFA (33%) > PANI‐Bi(OTf)₃ (27%) > PANI‐Cu(OTf)₂ (20%) > PANI‐Yb(OTf)₃ (15%). Molecular weights of PLLA synthesized using PANI‐MSA and PANI‐TFA are found to be 4385 and 4830, respectively. This methodology gives highly crystalline polymer with mushroom cap‐like morphology. Advantage of this methodology is the use of easily synthesizable, recyclable, easily handlable, cheaper, and eco‐friendly nature of the catalyst. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41147.     

Simultaneous Oxidation and Doping of Aniline to Polyaniline by Oxidative Template: Electrochemical Performance in Supercapacitor

Polyaniline salts containing sulfuric acid and cetyltrimethylammonium sulfate dopants were prepared by aqueous (PANI-Aq), emulsion (PANI-Em), and interfacial (PANI-In) polymerization pathways using cetyltrimethylammonium peroxodisulfate as an oxidative template. Formation of polyaniline was confirmed from infrared and X-ray diffraction spectral results. Value of conductivity (15 S cm^?1) of the polyaniline salt prepared by emulsion polymerization pathway was higher with that of the conventional polyaniline salt. PANI-Aq, PANI-Em, and PANI-In showed layered, flower petals, and nanorod and flower petals morphologies, respectively. These polyaniline salts were used as electrode in supercapacitor. Specific capacitance of PANI-Em, PANI-Aq, and PANI-In were 520, 484, and 474 F g^?1, which were higher than the conventional PANI-H₂SO₄ salt (390). Energy density was 26, 24.2, and 23.6 Wh kg^?1, respectively at a power density of 120 W kg^?1. After 3000 charge-discharge cycles, retention in the specific capacitance values of polyaniline salts was 86% (PANI-Em), 85.4% (PANI-Aq) and 76.1% (PANI-In).     

无机盐催化高酸值油脂酯化反应的研究

以高酸值油脂和甲醇为原料,研究了六种无机盐在生物柴油酯化反应中的催化活性。结果表明,硫酸氢钠的催化酯化活性最好,并得到最优化条件如下：醇酸物质的量10：1,反应温度70℃,反应时间300min,催化剂用量4％,酯化率达到90．5％。优化条件下,二次酯化率达到98％。且催化剂易回收,具有良好的重复使用性能。     

对甲基苯磺酸钙催化合成肉桂酸正丁酯的研究

制备了对甲基苯磺酸钙,研究了以对甲基苯磺酸钙催化肉桂酸和正丁醇的酯化反应,考察了醇酸摩尔比、反应时间和催化剂用量对反应结果的影响,对合成的产品用折光率、元素分析和红外光谱进行了表征。实验结果表明,对甲基苯磺酸钙催化合成肉桂酸正丁酯的最佳反应条件为:醇酸摩尔比为2∶1,催化剂用量1.2%(以肉桂酸的物质的量计),反应时间120min,反应温度为回流温度。在最佳反应条件下,肉桂酸正丁酯收率在95%以上。反应结束后,催化剂通过简单的相分离即可重复使用。对甲基苯磺酸钙重复使用5次后,其催化活性无明显下降,产品收率仍可达到80%以上。     

氯化亚锡催化合成肉桂酸丁酯的研究

以肉桂酸与正丁醇为原料,氯化亚锡(SnCl2.2H2O)作为催化剂合成肉桂酸丁酯。对影响酯化率的因素进行了探讨。结果表明,最佳反应条件为:正丁醇与肉桂酸的摩尔比为3∶1,催化剂用量为0.2 g/0.02 mol酸,反应温度140℃左右,反应时间为2 h,酯化率可达92.4%以上。     

催化酯化合成丁酸正丁酯的研究进展

固体催化剂代替硫酸作为酯化的催化剂,评述了对甲苯磺酸、甲烷磺酸盐、氨基磺酸、强酸性阳离子交换树脂、三氯化铁、二氯化锡、四氯化锡、硫酸铁铵、硫酸亚铁,硫酸铈、硫酸钛、硫酸氢钠、季铵盐、固体超强酸、杂多酸、分子筛等固体催化剂和酶催化酯化合成丁酸正丁酯的方法。     

甲基磺酸亚铈催化合成肉桂酸正丁酯的研究

研究了甲基磺酸亚铈催化肉桂酸和正丁醇的酯化反应,考察了醇酸摩尔比、反应时间和催化剂用量对反应结果的影响．对合成的产品用折光率、元素分析和红外光谱进行了表征。实验结果表明,甲基磺酸亚铈催化合成肉桂酸正丁酯的最佳反应条件为：醇酸摩尔比为2：1,催化剂用量1．0％（以肉桂酸的物质的量计）,反应时间120min,反应温度为回流温度。在最佳反应条件下,肉桂酸正丁酯收率在96％以上。反应结束后,催化剂通过简单的相分离即可重复使用。甲基磺酸亚铈重复使用5次后,其催化活性无明显下降,产品收率仍可达到90％以上。     

对甲基苯磺酸铜催化合成肉桂酸正丁酯的研究

制备了对甲基苯磺酸铜,研究了以对甲基苯磺酸铜催化肉桂酸和正丁醇的酯化反应,考察了醇酸摩尔比、反应时间和催化剂用量对反应结果的影响,对合成的产品用折光率、元素分析和红外光谱进行了表征。实验结果表明,对甲基苯磺酸铜催化合成肉桂酸正丁酯的最佳反应条件为：醇酸摩尔比为2：1,催化剂用量1.5%（以肉桂酸的物质的量计）,反应时间120min,反应温度为回流温度。在最佳反应条件下,肉桂酸正丁酯收率在95%以上。反应结束后,催化剂通过简单的相分离即可重复使用。甲基磺酸镧重复使用5次后,其催化活性无明显下降,产品收率仍可达到90%以上。     

氯化铁催化合成肉桂酸异丁酯

研究了氯化铁催化下的肉桂酸和异丁醇的酯化反应，得出的优惠条件是，酸醇比为１１０，催化剂用量为０．０９２５ｍｏｌ（对１ｍｏｌ肉桂酸），反应时间３ｈ。在优惠条件下转化率８５．８％。     

催化酯化合成丁酸正丁酯的研究进展

固体酸催化剂是能够代替硫酸作为酯化的催化剂。文章评述了对甲苯磺酸、甲烷磺酸盐、氨基磺酸、强酸性阳离子交换树脂、三氯化铁、二氯化锡、四氯化锡、硫酸铁铵、硫酸亚铁，硫酸铈、硫酸钛、硫酸氢钠、季铵盐、固体超强酸、杂多酸、分子筛等固体催化剂和酶催化酯化合成丁酸正丁酯的实验结果。     

硫酸铁铵催化合成肉桂酸甲酯

在十二水合硫酸铁铵催化下，由肉桂酸和甲醇发生酯化合成了肉桂酸甲酯，当０．０２ ｍ ｏｌ肉桂酸，０．２０ｍ ｏｌ甲醇和０．０１ ｍ ｏｌ催化剂一起回流７．０ ｈ，产品收率达８７．５％ 。     

氯化铁催化合成肉桂酸环己酯

研究了氯化铁催化下肉桂酸和环己醇的酯化作用,得出优惠条件是：酸醇比为１∶１０（ｍｏｌ）,催化剂用量为０．１８５ｍｏｌ（对１ｍｏｌ肉桂酸）,反应时间２．０ｈ,肉桂酸转化率为７３．４％。