Silica Gel Catalyzed Stereoselective Conversion of Dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates to Dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-2-butenedioates in Solvent-Free Conditions

Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by 1-hydroxy-2-acetonaphthone leads to vinyltriphenylphosphonium salts, which undergo aromatic electrophilic substitution reaction with conjugate base to produce dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates. Silica gel was found to catalyze conversion of dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates to dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-2-butenedioates in solvent-free conditions at 90°;C in fairly good yields.     

Synthesis of 1-[2-(1H-Indol-3-yl)ethyl]-4-acetyl-3-hydroxy-5-phenyl-1H-pyrrol-2(5H)-ones

Russian Journal of General Chemistry - 1-[2-(1H-indol-3-yl)ethyl]-4-acetyl-3-hydroxy-5-phenyl-1H-pyrrole-2(5H)-ones were synthesized by the short heating of a mixture of tryptamine, aromatic...     

Synthesis and Electrochemical Properties of 2-(4-R 1 -Phenyl)-6-(4-R 2 -phenyl)-4-phenyl-3,4-dihydro1,2,4,5-tetrazin-1(2 H )-yls

A new methodology for creating electroactive components for organic batteries, based on the construction of a molecular platform including stable 3,4-dihydro-1,2,4,5-tetrazin-1(2H)-yl radicals was described. A series of 2-(4-R1-phenyl)-6-(4-R2-phenyl)-4-phenyl-3,4-dihydro-1,2,4,5-tetrazin-1(2H)-yls with substituents of various nature was obtained. It was shown that the substituents R1 in the aromatic ring at position 2 of the tetrazinyl fragment influence the value of the oxidation potential in the radical, but do not influence the value of the reduction potentials, while the substituent R2 of the aromatic ring at position 6 influence the values of the reduction potentials and practically do not influence oxidation potential values. Based on the obtained electrochemical data, a correlation structure–potential value was revealed for the cathodic and anodic process, with the help of which triarylsubstituted 3,4-dihydro-1,2,4,5-tetrazin-1(2H)-yl radicals with high values of the electrochemical gap were obtained.     

2-氨基-6-氟-9-(4-羟基-3-羟甲基丁基)嘌呤的合成

报道了2-氨基-6-氟-9-(4-羟基-3-羟甲基丁基)嘌呤(1)的合成, 通过对起始原料2-氨基-6-氯-9-(4-乙酰氧基-3-乙酰氧甲基丁基)嘌呤(2)水解脱去乙酰基, 得到2-氨基-6-氯-9-(4-羟基-3-羟甲基丁基)嘌呤(3). 化合物3与三甲胺乙醇溶液在混合溶剂[V(THF)∶V(DMF)＝3∶1]中反应得到相应的氯化铵盐4, 然后与KF在DMF溶剂中反应, 得到化合物1. 产品经UV-vis, IR, ¹H NMR, ¹⁹F NMR和MS表征. 考察了反应温度、氟化试剂等因素对氟化反应的影响, 为6位含氟的嘌呤核苷类化合物的合成提供了一种直接、简易的新方法.     

Synthesis of bipyrazoles and pyrazoloisoxazoles from 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one

Phenylhydrazine or hydrazine react with 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one ( 1 ) to give 4-acetoacetyl-3-methylpyrazolin-5-ones 4 . The synthesis of bipyrazoles and pyrazoloisoxazoles from 4 are reported.     

Synthesis and Alkylation of 4-(2-Chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethylpiperidin-2-thione

4-(2-Chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethylpiperidin-2-thione, which was used for the synthesis of 2-allylthio-4-(2-chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine, was obtained by the reaction of 2-thienoyltrifluoroacetone with 2-chlorophenylphenylmethylenecyanothioacetamide or with a mixture of 2-chlorobenzaldehyde and cyanothioacetamide in the presence of N-methylmorpholine. The molecular and crystal structure of the piperidinthione have been established by X-ray crystallography.     

新显色剂1-(6-羟基-2-嘌呤基)-3-[4-(苯基偶氮)苯基]-三氮烯的合成及与镉的显色反应

合成了新显色剂1 (6 羟基 2 嘌呤基) 3 [4 (苯基偶氮)苯基] 三氮烯(简称HPAPT),研究了它的性质及其与镉显色反应的条件。实验表明,试剂的分子式为C17H13N9,相对分子质量为359,熔点127～129℃,各级酸离解常数为pKa1=4.1,pKa2=7.2,pKa3=10 7。在pH9.0～11.0的Na2B4O7 NaOH缓冲介质中,试剂与镉形成2∶1的红色络合物,表观摩尔吸光系数为2 25×105L·mol-1·cm-1,镉质量浓度在0～0.6mg/L范围内符合比耳定律,在联合掩蔽剂的作用下,可不经分离直接测定环境水样和工业废水中微量镉。     

Synthesis and reactions of 3-acetyl-6-methyl-2-(methylthio)pyridine

A reaction of methyllithium with 3-cyano-6-methylpyridine-2(1 H)-thione followed by alkylation of the resulting 3-acetylpyridinethione, or a direct reaction of methyllithium with 3-cyano-6-methyl-2-(methylthio)pyridine, afforded 3-acetyl-6-methyl-2-(methylthio)pyridine. The ketone obtained was examined in bromination reactions under various conditions. Bromi-nation in methanol or chloroform, proceeding through the formation of sulfonium bromides, gave substituted 3-(bromoacetyl)pyridine. A reaction of 3-acetyl-6-methyl-2-(methyl-thio)pyridine with N-bromosuccinimide in CCl4 afforded N-(pyridinesulfenyl)succinimide. The bromo ketone was used for the synthesis of various heterocyclic compounds.     

Synthesis of 1-(1-Adamantyl)-2-hydroxy-3-amino-3-R-propanones

Previously unknown cis-1-(1-adamantyl)-2,3-epoxy-3-R-propanones were highly selectively obtained by epoxidation of ,-unsaturated ketones with hydrogen peroxide in alkaline medium. The regioselectivity of the epoxide ring cleavage with amines (piperidine and morpholine) was studied.     

Synthesis of ethyl 5-cyano-6-hydroxy-2-methyl-4-(1-naphthyl)-nicotinate

A novel ethyl 5-cyano-6-hydroxy-2-methyl-4-(1-naphthyl)-nicotinate is successfully synthesized and the structure is determined by XRD, GC-MS analysis, element analysis and NMR spectroscopic in detail. A reaction mechanism for the reaction is proposed.     

Synthesis of 4-Acyl-5-aryl-3-hydroxy-1-(3-picolyl)-3-pyrroline-2-ones

Russian Journal of General Chemistry - Reaction of methyl esters of acylpyruvic acids with a mixture of aromatic aldehyde and 3-picolylamine gave...