3-(4-氨基苯基偶氮)苯磺酸钠的合成

氨基甲基苯基偶氮苯磺酸钠;3-(4-氨基苯基偶氮)苯磺酸钠的合成     

4—（4—氨基—3—甲基苯偶氮）苯磺酸的合成

４－（４－氨基－３－甲基苯偶氮）苯磺酸可做为染料中间体［１］．据其结构，一般认为可由对氨基苯磺酸重氮盐与邻甲苯胺通过偶合反应制备．初步实验表明，对氨基苯磺酸重氮盐与邻甲苯胺在弱酸及弱碱性介质下易发生氨基上的偶合反应，生成重氮氨基化合物；在强酸性介质下...     

2-氨基-4-甲氧基氯代苯甲酸的合成研究

以2-氨基-4-甲氧基苯甲酸甲酯为原料,通过氯代反应,再分别通过酯水解反应得到化合物2-氨基-5-氯-4-甲氧基苯甲酸和2-氨基-3-氯-4-甲氧基苯甲酸。其中间体及产物结构经~1H NMR、~(13)C NMR和ESI-MS确证,并考察了最佳氯代反应条件。结果表明:物料配比为n(2-氨基-4-甲氧基苯甲酸甲酯)∶n(NCS)=1∶1. 2,反应溶剂为N,N-二甲基甲酰胺,反应时间为16 h,两种氯代产物2-氨基-5-氯-4-甲氧基苯甲酸甲酯和2-氨基-3-氯-4-甲氧基苯甲酸甲酯收率分别为47%和39%。     

合成5－氯2－氨基苯膦酸的新方法

报道了以２．５－二氯苯胺为原料合成５－氯－２氨基苯膦酸的新方法，总产率达４１％，是文献报道的以间氯苯胺为原料的合成方法的总产率的近３倍。     

3-正丙基-4-氨基-5-酰胺基-1-甲基吡唑的合成

以2－戊酮为起始原料，经Claisen缩合、环化、甲基化、皂化、硝化、酰胺化和还原反应，制得目标化合物。总收率比文献报道值提高一倍，达46．8％。     

用二氧化硫脲合成4—甲基—4‘—氨基二苯醚的研究

4甲基4′氨基二苯醚是合成农药、染(颜)料、医药的重要中间体.传统的制备方法是由4 甲基4′硝基化合物(简称硝基物)在盐酸存在下用二氯化锡还原得到[1] ,该方法工艺成熟、产品质量好,但产率低,污染严重.陈其亮等报道了由硝基物催化加氢的方法[2],但存在设备投资大,操作繁锁等缺点.二氧化硫脲(Thiourea dioxide ,简称TD)是一种非常优良的还原剂,已广泛应用于有机合成的许多方面[3,4],但应用于标题化合物的制备未见报道,本文对此进行了研究,收到较好效果.合成路线如下:     

(4R,5S)-5-羟基-4-甲基-3-己酮的合成

农业害虫药材甲Stegobium panicem Linnae在我国各省区都有分布,主要危害谷类、食品、药材、图书、档案等.我国一般每年可以发2～3代,温度较高的地区可发生4代[1] .     

2-氨基-4''-溴-二苯甲酮的合成

2-氨基-4'-溴-二苯甲酮(1)是植物生长调节剂及园艺用杀菌剂异菸碱酰替苯胺的关键中间体[1] ,也是医药原料的重要中间体,可用于合成治疗眼科发炎类药物[2].文献合成路线如下:     

3-苄基-4-氨基-5-芳胺基-1,2,4-三唑的合成与表征

酰氨基硫脲是一类重要的有机合成中间体[1-3]。其最终产物大都有消炎、镇痛、抗菌、杀虫、除草、调节植物生长等生理活性。本文以苯乙酸乙酯与芳胺为基本原料,经多步反应,制得1 苯乙酰基 4 芳基氨基硫脲,研究了它们在水合肼存在下的关环反应,合成了3 苄基 4 氨基 5 芳胺基 1,2,4 三唑,其结构经元素分析、红外光谱、核磁共振氢谱、碳谱表征。1　实验部分1 1　仪器与试剂ＸＴ4Ａ型显微熔点仪(温度计未校正);ＣＥ公司(意大利)Ｆｌａｓｈ1112型自动元素分析仪;Ｂｒｕｋｅｒ公司(德国)Ｅｑｕｉｎｏｘ55型红外分光光度计,ＫＢｒ压片;Ｂｒｕｋ…     

Electrosynthesis of 5-amino-4-oxopentanoic acid hydrochloride

The electroreduction of methyl 5-nitro-4-oxopentanate was studied by means of a polarographic method and preparative electrolysis in acidic-alcoholic solutions. The effects of the following factors on the yield and quality of 5-amino-4-oxopentanoic acid hydrochloride were studied: the cathode material, amount of electricity, temperature, nature of the solvent, concentrations of the initial nitro compound and hydrochloric acid, and the cell design. It was shown by electrolysis at a controlled potential and in a galvanostatic mode that the products of methyl 5-nitro-4-oxopentanate electroreduction are hydroxyamino and amino compounds, and also ammonium chloride, nitromethane, methylhydroxylamine hydrochloride, and monomethylamine hydrochloride. Their ratio depends on the electrolysis conditions. The highest overall substance yield (61.1–66.0%) and current yield (68.1–68.6%) of 5-amino-4-oxopentanoic acid hydrochloride was achieved at a copper cathode in a filter-press cell. The content of the main substance in the electrochemically obtained samples of 5-amino-4-oxopentanoic acid was 89.5–91.0%.     

Synthesis and characterization of Boc-protected 4-amino- and 5-amino-pyrrole-2-carboxylic acid methyl esters

Syntheses of Boc-protected 4-amino- and 5-amino-pyrrole-2-carboxylic acid methyl esters have been achieved and the structures of these compounds have been fully characterized by detailed NMR studies.     

Novel synthesis of 2-amino-3-hetaryl-4(5H)-oxothiophenes

3-Cyano-3-hetaryl-2-oxopropyl thioacetates were obtained by the acylation of hetarylacetonitriles with acetylmercaptoacetyl chloride. Their reaction with amines led to the formation of 2-amino-3-hetaryl-4(H)-oxothiophenes. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 680–685, May, 2006.     

Electroorganic synthesis of 6-aminonicotinic acid from 2-amino-5-chloropyridine

A synthesis of 6-aminonicotinic acid by electrochemical hydrogenation of 5-chloro-2-nitropyridine and electrochemical carboxylation of 2-amino-5-chloropyridine at a cathode surface in the presence of sulphuric acid and carbon dioxide in a dimethylformamide (DMF) solution at an apparent current density of 10 mA/cm² using an undivided cell with good yields is reported.     

2-(4-正戊氧基苯基)-5-氯-嘧啶的合成

以氯乙酸为原料制得高氯酸盐，产率84％，进而与对正戊氧基苯甲脒盐酸盐相对接，全盛了2-(4-正戊氧基苯基）－5－氯－嘧啶，收率90％。通过元素分析，核磁共振谱证实了其结构。总产率75％（以氯乙酸计算）。     

Novel synthesis of 2-butyl-5-chloro-3H-imidazole-4-carbaldehyde： A key intermediate of Losartan

A novel method for synthesis of 2-butyl-5-chloro-3H-imidazole-4-carbaldehyde 2, a key intermediate of Losartan was reported. The compound 2 was synthesized from starting material dimethyl malonate 6 and n-valeronitrile 8 by six steps with an overall yield of 40%.The key step including the reaction of compound $ with POCI3/DMF followed by hydrolysis to give compound 2 with the yield of 68%.     

A highly enantioselective synthesis of 5-(l-menthyloxy )-4-substituted-3-chloro-2(5H )-furanones

In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, 5-(l-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5–(l-menthyloxy)-4-substituted-3-chloro-2(5H)-furanones, were obtained in good yields with d. e. ? 98% under mild conditions.     

丝瓜络炭磺酸的制备及其催化合成糠醛

以丝瓜络为炭源、浓硫酸为磺酸化试剂,制备了丝瓜络炭磺酸催化剂。利用中和滴定、X射线衍射、傅里叶变换红外光谱和热重-差热分析等手段对催化剂进行了表征。以表面酸密度为考察指标,确定了在300℃炭化3h、在80℃下磺化3h为优化的催化剂制备条件,此条件下丝瓜络炭磺酸催化剂表面酸密度可达1.119mmol/g。以木糠水解制备糠醛为探针反应,通过正交实验法考察了催化剂的实际催化活性。结果表明,在水解反应时间2h、水解反应温度200℃和催化剂用量占原料质量10%时,糠醛的平均收率达到78.69%,此时催化剂的催化活性最高。催化剂经第一次循环使用后性能有所下降,但随后的循环使用催化性能稳定。将使用过的催化剂经再磺化,可基本恢复到新制催化剂的催化活性。