Preparation and characterization of symmetrical bis[4-chloro-2-pyrimidyl] dichalcogenide (S, Se, Te) and unsymmetrical 4-chloro-2-(arylchalcogenyl) pyrimidine: X-ray crystal structure of 4-chloro-2-(phenylselanyl) pyrimidine and 2-(p-tolylselanyl)-4-chloropyrimidine

Synthesis of a novel class of multinucleate pyrimidine chalcogen (S/Se/Te) derivatives has been successfully attempted for the first time by the selective substitution of chlorine at the C-2 position of 2,4-dichloropyrimidine with nucleophilic dichalcogenide anion E₂²⁻ (E = S, Se, Te) to afford bis[4-chloro-2-pyrimidyl] dichalcogenide. The highly electrophilic nature of 2,4-dichloropyrimidine compared to aryl chlorides has been further exploited to prepare a variety of 4-chloro-2-(arylchalcogenyl) pyrimidine compounds by substituting the chlorine exclusively at the C-2 position of 2,4-dichloropyrimidine with a variety of chalcogen bearing aryl anions ArE⁻ (Ar = phenyl, 1-naphthyl, p-tolyl, 4,6-dimethyl-2-pyrimidyl, 2-pyridyl, 4-methyl-2-pyridyl). All the newly prepared symmetrical and unsymmetrical pyrimidyl chalcogen compounds have been thoroughly characterized with the help of various spectroscopic techniques viz., NMR (¹H, ¹³C, ⁷⁷Se), FT-IR and mass spectrometry (in representative cases). The crystal structures of 4-chloro-2-(phenylselanyl) pyrimidine and 2-(p-tolylselanyl)-4-chloropyrimidine have been determined by X-ray crystallography.     

Reactions of 2-chloro-2-(4-pyridyl)propane with nucleophiles. Substitution on tertiary carbon

The reaction of 2-chloro-2-(4-pyridyl)propane ( 2 ) with lithium 2-propanenitronate affords the C-alkylation product 2-nitro-3-(4-pyridyl)-2,3-dimethylbutane ( 3 ), the Michael-adduct 2-nitro-2-methyl-4-(4-pyridyl)pentane ( 4 ), 4-isopropenylpyridine ( 5 ) and 2-(4-pyridyl)-2-propanol ( 6 ). Of these four products, only the formation of 3 is suppressed when the reaction is performed in the presence of radical inhibitors. The reaction of compound 2 with sodium azide gives the tertiary substitution product 2-azido-2-(4-pyridyl)propane ( 8 ). The reaction is not influenced by radical inhibitors. This is also the case in the reaction of 2 with sodium benzenethiolate, which affords 2-mercaptophenyl-2-(4-pyridyl)propane ( 9 ) and 1-mercaptophenyl-2-(4-pyridyl)propane ( 10 ). Compound 5 , the product of an E₂-type elimination is also formed in the azide and thiolate reactions. A Michael type addition of sodium benzenethiolate to 5 explains the formation of 10 . Similarly, generation of 5 in reactions of 2 with sodium methanethiolate and sodium cyanide accounts for the formation of 1-mercaptomethyl-2-(4-pyridyl)propane ( 11 ) and 3-(4-pridyl)butanenitrile ( 12 ), respectively.     

Synthesis and characterization of chalcogen (S and Se) derivatives of 4-chloro- and 4-methoxy-N,N-diisopropylpyridine-2-carboxamide: X-ray structure of 4-methoxy-3-(sulfanylmethyl)- and 4-chloro-3-(selenenylbenzyl)-N,N-diisopropylpyridine-2-carboxamide

Synthesis of chalcogen (S and Se) derivatives of 4-chloro- and 4-methoxy-N,N-diisopropylpyridine-2-carboxamide (1a and 1b respectively) has been reported. 1a and 1b were lithiated with 2 equiv. of n-BuLi or LDA at ?78 °C. Addition of elemental sulfur or selenium to the carbanion led to the formation of corresponding thiolate or selenolate anions respectively. The selenolate anions were aerial oxidized to afford the corresponding diselenides. The thiolate/selenolate anions were quenched with a variety of electrophiles to give unsymmetrical thio/selenoalkanes in moderate to good yields. Reductive cleavage of Se–Se bond has also been studied. The synthesized compounds were characterized by elemental analysis, NMR (¹H, ¹³C and ⁷⁷Se), FT-IR and mass spectral techniques. Crystal structures of two compounds, 6b and 7a, were determined by single crystal X-ray crystallography. Their crystal structure exhibits 1,4-type S?OCH₃ and Se?Cl intramolecular secondary interactions respectively. The relative thermal stability of 3a, 3b and 4a has also been established by thermogravimetric analysis.     

Indole derivatives. 135. 5-[2-(4-Methoxyphenyl)ethenyl]indolines and indoles

5-[2-(4-Methoxyphenyl)ethenyl]indolines were obtained from 5-formyl-1-methyl- or 5-forrayl-1-benzylindolines by the Witting reaction with 4-methoxybenzylidenetriphenylphosphorane. Their dehydrogenation led to the formation of the corresponding compounds of the indole series. The corresponding hydroxy compounds were obtained by demethylation of the methoxyindole with boron tribromide and were converted into the acetoxy derivatives of indoline and indole.For communication 134, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 911–914, July, 1989.     

Enantioselective syntheses of no-carrier-added (n.c.a.) (s)-4-chloro-2-[f] fluorophenylalanine and (s)-(α-methyl) -4-chloro-2-[f]fluorophenylalanine

(S)-4-Chloro-2-fluorophenylalanine and (S)-(α-methy)-4-chloro-2-fluorophenylalanine were synthesized and labeled with no carrier added (n.c.a.) fluorine-18 through a radiochemical synthesis relying on the highly enantioselective reaction between 4-chloro-2-[¹⁸F]fluorobenzyl iodide and the lithium enolate of (2S)-1-(tert-butyloxycarbonyl)-2-(tert-butyl)-3-methyl-1,3-imidazolidine-4-one for (S)-4-chloro-2-[¹⁸F]fluorophenylalanine and (2S,5S)-1-(tert-butyloxycarbonyl)-2-(tert-butyl)-3,5-dimethyl-1,3-imidazolidine-4-one for (S)-(α-methyl) -4-chloro-2-[¹⁸F] fluorophenylalanine. Quantities of about 20–25 mCi were obtained at the end of sy nthesi s, ready for injection after hydrolysis and high performance liquid chromatography (HPLC) purification, with a radiochemical yield of 17%–20% corrected to the end of bombardment after a total synthesis time of 90–105 min from [¹⁸F] fluoride. The enantiomeric excesses were shown to be 97% or more for both molecules without chiral separation and the radiochemical and chemical purities were 98% or better.     

Reactions of 3-methyl-1-(2-pyridyl)-4-chloro-5-formyl-6,7-dihydroindazole

The reactions of 3-methyl-1-(2-pyridyl)-, 3-methyl-1-phenyl-, and 3-methyl-1,6-diphenyl-4-chloro-5-formyl-6,7-dihydroindazoles with guanidine and benzo- and 3- and 4-pyridinecarbamidines gave the corresponding 8-substituted 1-methyl-3-(2-pyridyl)-and 1-methyl-3-phenyl-4,5-dihydropyrazolo[5,4-h]quinazolines. With acetic anhydride the same indazole derivatives gave the 4-acetoxy-5-formyl derivatives, and with hydroxylamine they gave4-chloro-5-hydroxyiminomethyl-6,7-dihydroindazoles. Thereactionof4-acetoxyl-1-(2-pyridyl)-5-formyl-6,7-dihydroindazole with hydroxylamine gave 8-methyl-6-(2-pyridyl)-4,5-dihydroisoxazolo[5,4-e]indazole, while dehydration of 5-hydroxyiminomethyl-3-methyl-4-chloro-6,7-dihydroindazole gave the 4-chloro-5-cyano derivative. The reaction of the latter with nucleophilic reagents was investigated.Riga Technical University, Riga, Latvia LV-1658. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1209–1213, September, 1998.     

Crystal structure of bis(2-(2-thiazolylazo)-4-methylphenol)cobalt(III)chloride.

The reaction between CoCl2 x 6H2O and 2-1-(2-thiazolylazo)-p-cresol (TAC) in acetone resulted in six coordinated cobalt(III) complex, [Co(TAC)2]Cl3. Two TAC ligands coordinate with cobalt ion forming four five membered chelate rings. The cobalt ion is octahedrally coordinated by a phenolic oxygen, azo nitrogen and nitrogen in thiazole rings. Three chloride ions are disordered.     

Synthesis of N,N,N-Triethyl-2-[4-(2-phenylethenyl) phenoxy] ethanammonium iodide

The synthesis of N,N,N-triethyl-2-[4-(2-phenylethenyl) phenoxy] ethanammonium iodide, antispasmodic disubstituted olefin, was achieved via palladium-catalyzed cross-coupling of phenylacetylide with aryl bromide followed by hydroalumination.     

Binary pnictogen azides--an experimental and theoretical study: [As(N3)4]-, [Sb(N3)4]-, and [Bi(N3)5(dmso)]2-

[PPh(4)][EI(4)] (E=As, Sb, Bi) salts were reacted with four and five equivalents of AgN(3) to form tetraazidopnictates and pentaazidopnictates of the type [PPh(4)][E(N(3))(4)] and [PPh(4)](2)[E(N(3))(5)], respectively. The synthesis of [PPh(4)][P(N(3))(4)] was also attempted from the reaction of P(N(3))(3) with [PPh(4)]N(3), but it yielded only the starting materials. Herein, we report the synthesis and structure elucidation of [PPh(4)][E(N(3))](4) (E=As, Sb) and pentaazidobismuthate, stabilized as the dimethyl sulfoxide (DMSO) anion adduct, [PPh(4)](2)[Bi(N(3))(5)(dmso)]. Successive anion formation along the series E(N(3))(3)+nN(3)(-) (n=1-3) and E(N(3))(5)+N(3)(-) was studied by density functional theory.     

The unexpected formation of a lithium-enolate from bis2-[(dimethylamino)methyl]phenyl copper lithium. X-ray structure of Li4[OC(CH2)C6H4CH2NMe2-2]4

Attempted crystallization of the bis(aryl)lithium cuprate, Cu₂Li₂(C₆H₄CH₂-NMe₂-2)₄, from diethyl ether/pentane afforded in according to an X-ray diffraction analysis appeared to be the lithium enolate, Li₄[OC(=CH₂)C₆H₄CH₂NMe₂-2]₄. This consists of a central Li₄O₄ cube with intramolecular LiN coordination of the CH₂NMe₂ substituent. This enolate, which has also been prepared via an independent route, is the first example of a structurally characterized lithium enolate and contains Li centres that are intramolecularly coordinated.     

Synthesis of 4-(4-Alkyl-2-morpholinyl)indoles

N-substituted 4-(2-morpholinyl)indoles were prepared from 1-(t-butoxycarbonyl)-4-acetylindole (7) which was itself prepared from 4-cyanoindole. Bromination of ketone 7, followed by reaction with amines and subsequent sodium borohydride reduction, gave amino alcohols. These were converted to α-chloro amides that were cyclized to lactams. Lithium aluminum hydride reduction served both to remove the t-BOC protecting group and to reduce the lactams to the 4-(2-morpholinyl) indoles.     

3-氯-4-二苄胺基-5-甲氧基-2(5H)-呋喃酮的合成与晶体结构

在THF溶液中合成了标题化合物3-氯-4-二苄胺基-5-甲氧基-2(5H)-呋喃酮,并用FT-IR、UV-Vis、1HNMR、13C NMR、MS、元素分析和X-射线衍射等进行了表征。结果表明此化合物属正交晶系,空间群为Pbca,晶胞参数为:a=15.891(16),b=11.126(11),c=19.778(19),α=β=γ=90°,V=3497(6)3,Z=8,Dc=1.306Mg/m3,μ=0.234 mm-1,F(000)=1440。在化合物的分子结构中,两个苯环几乎垂直于呋喃酮平面,且它们与呋喃酮平面的两面角分别为89.38°和88.19°。     

One-step synthesis of 5-acetyl-2-amino-4-aryl-3-cyano-4H-pyrano[3,2-b]indoles. Molecular and crystal structure of 5-acetyl-2-amino-4-(4"-chloro-3"-nitrophenyl)-3-cyano-4H-pyrano[3,2-b]indole

A one-step procedure was developed for the synthesis of 5-acetyl-2-amino-4-aryl-3-cyano-4H-pyrano[3,2-b]indoles involving the three-component reaction of 1-acetylindol-3(2H)-one with aromatic aldehydes and malononitrile in ethanol in the presence of triethylamine as the catalyst. The structure of 5-acetyl-2-amino-4-(4"-chloro-3"-nitrophenyl)-3-cyano-4H-pyrano[3,2-b]indole was established by X-ray diffraction analysis.     

N，N’-二[3-氯-5S-（l-孟氧基）-2（5H）-4-呋喃酮基]-1，4-丁二胺的合成及晶体结构

合成了N,N’-二[3-氯-5S-（l-孟氧基）-2（5H）-4-呋喃酮基]-1,4-丁二胺,并通过IR,^1H NMR,MS和X射线单晶衍射对其进行了表征．X射线单晶衍射结果表明：标题化合物的不对称结构单元中包含一个平面的呋喃酮环和一个椅式的环己烷环,四个手性中心．标题化合物通过N—H…O分子间氢键作用实现空间堆积．