Hexa(organylsilsesquioxanes)

A method for the synthesis of earlier practically unknown hexa(organylsilsesquioxanes) (RSiO_1,5)₆ have been developed based on the reaction of organyltrichlorosilanes RSiCl₃ (R = Et, Vin) with DMSO. The reaction proceeded in several steps. The initial stage of the reaction gave poorly available 1,3,5-trichloro-1,3,5-triorganylcyclosiloxanes in 40—80% yield, as well as organyl(chloro)oligohomosilsesquioxanes, which further are converted to the corresponding organyloligosilsesquioxanes. Based on the monitoring of the reaction mixture by GC-MS, a scheme for the formation of the intermediate silsesquioxane structures have been suggested.     

超声辅助快速合成4H-吡喃衍生物

采用浸渍法制备水滑石（LDH）负载路易斯酸催化剂,并通过傅里叶红外（FT-IR）、热重分析（TG）和扫描电子显微镜（SEM）对其结构进行分析。以芳香醛、丙二腈及苯甲酰乙腈为原料,LDH负载路易斯酸为催化剂,超声辅助快速合成4H-吡喃衍生物。采用单因素法研究了催化剂、溶剂、超声时间、原料摩尔比、催化剂用量、催化剂循环等对产率的影响。结果表明:超声辅助下,LDH/ZnCl₂催化5 min即可合成4H-吡喃衍生物(4a~4i),产率82.8%~98.2%;扩大原料用量至克级,4a产率94.6%,且催化剂循环5次仍保持较高的催化性能。      

Rapid Syntheses of Benzyl Acetate Under Microwave Irradiation

ＲａｐｉｄＳｙｎｔｈｅｓｅｓｏｆＢｅｎｚｙｌＡｃｅｔａｔｅＵｎｄｅｒＭｉｃｒｏｗａｖｅＩｒｒａｄｉａｔｉｏｎＪＩＡＮＧＹｕ－Ｉｉｎ;ＹＵＡＮＹｕｎ－ｃｈｅｎｇ;ａｎｄＳＵＮＹｕｅ－ｈｕａ（ＳｃｈｏｏｌｏｆＣｈｅｍｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ,Ｄａｌ...     

六苯基苯衍生物分子内光化学关环反应

研究了六苯基苯衍生物的分子内光化学关环脱氢反应,与热化学关环脱氢反应不同,光化学关环脱氢反应只生成关一个环的产物。光化学关环脱氢反应过程中,氧化剂种类、用量以及溶剂对关环脱氢产物的产率具有显著影响,在正己烷溶剂中,以单质碘为氧化剂进行光化学关环脱氢反应,关环产物产率可达91%。     

一种无计有机聚合物中间体——六(甲基丙烯酸羟乙酯)三聚膦腈的合成

六氯三聚膦腈;一种无计有机聚合物中间体——六(甲基丙烯酸羟乙酯)三聚膦腈的合成     

磷酰化线氨酸六配位磷中间体的结构及其反应

用ＭＮＤＯ方法对磷酰化丝氨酸仿生化反应机理中所形成的六配位磷中间体（３）可能的３个异构体的结构及其反应活性进行了研究。在六配位磷中间体３的６根键中,丝氨酸的羧基氧Ｏ３与磷之间的键最弱,最易断裂生成新的五配位磷中间体４,４的Ｐ－Ｎ键断裂得到磷酰基的Ｎ→Ｏ转位反应产物５。对于六配位磷中间体３中的两个异丙氧基,位于丝氨酸铡链羟基Ｏ６对面的异丙氧基较另一个易于离去（约低３７ｋＪ／ｍｏｌ）并得到中间体６,接     

Hexa boron-dipyrromethene cyclotriphosphazenes: synthesis, crystal structure, and photophysical properties

We have synthesized four examples of a cyclotriphosphazene ring appended with six boron-dipyrromethene dyes N(3)P(3)(BODIPY)(6) by adopting two different methods. In method I, 1 equiv of N(3)P(3)Cl(6) was treated with 6 equiv of meso-(o- or m- or p-hydroxyphenyl)boron-dipyrromethene in tetrahydrofuran (THF) in the presence of cesium carbonate. This afforded N(3)P(3)(BODIPY)(6) in yields ranging from 80 to 90%. In method II, we first prepared hexakis(p-formylphenoxy)cyclotriphosphazene N(3)P(3)(CHO)(6) by treating 1 equiv of N(3)P(3)Cl(6) with 6 equiv of 4-hydroxybenzaldehyde in the presence of cesium carbonate in THF. In the second step, N(3)P(3)(CHO)(6) was condensed with excess of pyrrole in the presence of catalytic amount of trifluoroacetic acid (TFA) in CH(2)Cl(2) at room temperature and afforded hexakis(p-phenoxy dipyrromethane)cyclotriphosphazene. In the last step, the hexakis(p-phenoxy dipyrromethane)cyclotriphosphazene was first oxidized with 6 equiv of DDQ in CH(2)Cl(2) at room temperature for 1 h followed by neutralization with triethylamine and further reaction with excess BF(3)·Et(2)O afforded the target N(3)P(3)(BODIPY)(6) in 16% yield. The route II was used only for the synthesis of one target compound whereas the route I was used for the synthesis of all four target compounds. The four compounds were characterized by mass, NMR, absorption, electrochemical, and fluorescence techniques. The crystal structure solved for one of the compounds revealed that the P(3)N(3) ring is slightly puckered and the six substituents were not interacting with each other and attained pseudo-axial and pseudo-equatorial positions. The photophysical studies in five different solvents indicated that the compounds exhibit large Stokes' shifts unlike reference monomeric BODIPYs indicating that the compounds are promising for fluorescence bioassays. The quantum yields and lifetimes of compounds 1-4 depends on the type of BODIPY unit attached to the cyclotriphosphazene ring.     

Synthesis and Structure of Hexa(Diethoxyphosphoryloxy)calix[6]arene

Abstract

Hexapodand 1, which contains six phosphoryl groups at the lower rim of the macrocycle, was synthesized by the reaction of calix[6]arene with diethylchlorophosphate and sodium hydride. The structure is confirmed by X-ray studies: C₆₆H₉₀O₂₄P₆, Pbca, a = 14.867 (4), b = 18.577 (4), c = 26.510(6), D_c = 1.265g/cm³, Z = 4, and R = 0.063 for the 4600 observed reflections. The molecule 1 exists in a centrosymmetrical flattened 1,2,3-alternate conformation, in which diametrically opposed benzene rings are parallel. Four phosphoryl groups are oriented away from the cycle, two other groups are self-included in the macrocycle cavity.     

Cascade Claisen Rearrangement: Rapid Synthesis of Polysubstituted Salicylaldehydes and Total Syntheses of Hemigossypol and Gossypol

A cascade Claisen rearrangement of a well‐organized maltol propargyl ether for the construction of polysubstituted salicylaldehydes is reported. This reaction features high atom economy (100 %), as well as catalyst‐free and gram‐scale conditions. Based on this novel methodology, the total synthesis of hemigossypol, gossypol, and their analogues has been realized.     

六对羧基苯氧基环三磷腈的合成及其热性能

羧基苯氧基磷腈及其衍生物由于具有优良的生物活性并能降解成无毒产物,因而在生物医用材料的应用上潜力巨大。本文采用两步法合成了六对羧基苯氧基环三磷腈(HCPCP),首先以六氯环三磷腈和对羟基苯甲醛为原料,采用亲核取代反应制得六对醛基苯氧基环三磷腈（HAPCP）,再用KMnO4氧化法合成HCPCP。通过红外光谱、高效液相色谱、核磁共振及元素分析等确证了产物的结构;用TGA和DSC对其热性能进行了研究。     

Synthesis,Characterization, and Spectroscopic Properties of Hexa(4-Bromo-2-Formyl-Phenoxy)Cyclotriphosphazene and Hexa(4-Chloro-2-Formyl-Phenoxy)Cyclotriphosphazene and Fully Substituted Cyclotriphosphazene Derivatives Bearing a Schiff Base at Room Temperature

Abstract

Hexa(4-bromo-2-formyl-phenoxy)cyclotriphosphazene (2) and hexa(4-chloro-2- formyl-phenoxy)cyclotriphosphazene (3) were obtained from the reactions of hexachloro- cyclotriphosphazene (1) with 5-bromosalicylaldehyde and 5-chlorosalicylaldehyde in the presence of (C₂H₅)₃N and K₂CO₃ at room temperature, respectively. The new two organocyclotriphosphazenes bearing formyl groups were reacted with 4-cyano aniline, 2-phenyl aniline, 4-aceto aniline, 5-chloro-2-hydroxy aniline, 2-hydroxy aniline, 4-hydroxy aniline, 2-(4-morpholino)ethyl amine, 4-carboxy aniline, 4-carbomoyl aniline, 2-mercapto aniline, and 5-amino isoquonoline to prepare cyclotriphosphazene derivatives containing a Schiff base at room temperature. However, fully phenoxy-substituted cyclotriphosphazenes containing a Schiff base were isolated from the reactions of the compound 2 and 3 with 5-chloro-2-hydroxy aniline, 2-hydroxy aniline, 4-hydroxy aniline, and 2-(4-morpholino)ethyl amine. The structures of the synthesized compounds were characterized by elemental analysis, IR, and NMR (¹H, ¹³C, ³¹P) spectroscopy. According to the results of the analysis, all synthesized compounds were found to be fully substituted organocyclotriphosphazenes, such as hexa[4-bromo-2-(5-chloro-2-hydroxy-pheyliminomethyl)phenoxy]cyclotriphosphaze (2a). All cyclotriphosphazene derivatives synthesized gave fluorescence emission peaks in range between 300 nm and 410 nm.     

Physico-chemical Studies on Zinc Hexa(formato)ferrate(III) Decahydrate

Thermal analysis of zinc hexa(formato)ferrate(III) decahydrate, Zn₃ [Fe(HCOO)₆]₂ 10H₂O has been investigated up to 800°C in static air atmosphere employing TG, DSC, XRD, IR, ESR and Mössbauer spectroscopic techniques. After dehydration at 160°C, the anhydrous complex decomposes into α-Fe₂ O₃ and zinc carbonate in successive stages. Subsequently the cations remix to yield fine particles of zinc ferrite, ZnFe₂ O₄ , as a result of solid state reaction between α-Fe₂ O₃ and zinc carbonate at a temperature (600°C) much lower than for ceramic method.     

Hexa(2-pyridyl)[3]radialene: self-assembly of a hexanuclear silver array

Reaction of the new ligand hexa(2-pyridyl)[3]radialene with silver tetrafluoroborate results in the formation of a M6L2 cage with an encapsulated mu 3-fluorido anion.     

Syntheses of di- and tetrahydropyrroles

It is shown by means of IR and PMR spectra that the products of the aminolysis of esters of 3,3-dimethyl(2-carbethoxy)levulinic acid and -chloro-,,-trimethylbutyrolactone exist in the cyclic form of 2-hydroxy-5-pyrrolidones (Ia-d). It was established by PMR spectroscopy that, except for the 4-carbamido derivative (Id), these compounds undergo spontaneous dehydration in anhydrous solutions. In addition, ring-chain tautomeric equilibrium is established in solutions of the N-phenyl derivative (Ib). The rates of establishment of equilibrium and the equilibrium positions were investigated for both processes.See [1] for communication VIII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 22–26, January, 1973.     

Syntheses of silatranyl- and germatranyluridines

[reaction: see text] Silatranyluridine 1 and germatranyluridine 2 have been prepared in five steps from oxazolinouridine 3 in 27 and 29% yields, respectively. These compounds are novel transition-state analogues (TSAs) for RNA hydrolysis and offer a number of advantages over traditional vanadium- or rhenium-based TSAs. Germatrane 2 is completely stable in D(2)O at room temperature, and the half-life of silatrane 1 in D(2)O was found to be >7 days by (1)H NMR spectroscopy.     

Syntheses of Benzoxepinoquinolinone and Benzothiepinoquinolinone

l-Benzoxepino(3, 4-b)quinolin-l3(6H)-one and its halogen,alkyl, alkoxy derivatives Va'-d' and 1-benzothiepino(3,4-b}-quinolin- 13 ( 6H)-one Vf, and its alkyl derivatives Vg, weresynthesized through cyclization of 2-(substituted phenoxymethyl)-3-quinolinecarboxylic acids Va-d and 2-[ (un)substituted phen-ylthiomethyll-3-quinolinecarboxylic acids IVf-g in the presence ofpolyphosphoric acid.The acids IV were obtained from the corresponding ethyl-esters @ whcih were prepared through refluxing ethyl 2-bromo-methyl-3-quinolinecarboxylate(1) with substituted phenol or (un)substituted thiophenol in the presence of NaOEt.The compound Vg, was allowed to react with NBS, KaBH4, NH2OH-HCl to give compounds VII , VIII, and IX, respectively.The structures of 24 new compounds have been confirmed by elemental analysis, IR and 1H NMR.