Synthesis and herbicidal activity of (Z)-ethoxyethyl 2-cyano-3-(2-methylthio-5-pyridylmethylamino)acrylates

2-Methylthio-5-pyridinemethylene amine was prepared from 2-chloro-5-methylpyridine. Ethoxyethyl 2-cyano-3,3-dimethylthioacrylate was prepared from ethoxyethyl cyanoacetate, carbon disulfide, and dimethyl sulfate in 86.2% yield. Its reaction with 2-methylthio-5-pyridinemethylene amine yielded (Z)-ethoxyethyl 2-cyano-3-methylthio-3-(2-methylthio-5-pyridylmethylamino)acrylate. Ethoxyethyl (Z+E)-2-cyano-3-ethoxyacrylate was synthesized from ethoxyethyl 2-cyanoacetate and triethyl or- thoacetate in 90.7% yield, and its reaction with 2- methylthio-5-pyridinemethylene amine yielded (Z)-ethoxyethyl 2-cyano-3-methyl-3-(2-methylthio-5-pyri-dylmethylamino)acrylate. The structures of all of the products were confirmed by ¹H NMR, elemental analysis, IR, and mass spectroscopy. The herbicidal activities of the products were evaluated, and the results of bioassay showed that (Z)-ethoxyethyl 2-cyano-3-methyl-3-(2-methylthio-5-pyridylmethylamino)acrylate exhibits good herbicidal activity on rape (Brassica napus) at a dose of 1.5 kg/ha. © 2003 Wiley Periodicals, Inc. 15:67–70, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/.hc10214     

Synthesis of 6-substituted 3-cyano-5-nitropyridine-2(1H)-thiones

The reactions of 1-substituted 2-nitro-3-phenylaminoprop-2-en-1-ones with cyanothioacetamide afforded the corresponding 6-substituted 3-cyano-5-nitropyridine-2(1H)-thiones, which were used for the synthesis of 6-substituted 3-cyano-2-methylthio-5-nitropyridines and 7-substituted 4-hydroxy-8-nitropyrido[2",3":4,5]thieno[2,3-b]pyridin-2(1H)-ones.     

Synthesis of 6-amino-2-aryl-1,2-dihydro-3H-pyrido[2,3-d]pyrimidin-4-one derivatives

This paper reports the synthesis of new pyrido[2,3-d]pyrimidin-4-one derivatives as diuretic agents. Starting with 1,2-dihydro-5-nitro-2-oxo-3-pyridinecarboxylic acid 1 , ethyl 2-ethoxy-5-nitro-3-pyridincarboxylate 4 was obtained. Compound 4 reacts with ammonia, methylamine or S-methylpseudothiourea to give the respective 2-amino-5-nitro-3-pyridinecarboxamide derivatives 5 and 6 or 2-methylthio-6-nitro-3H-pyrido[2,3-d]pyrimidin-4-one 8. Treating carboxamide 5 with arylaldehydes and zinc dichloride, new 2-aryl-1,2-dihydro-6-nitro-3H-pyrido[2,3-d]pyrimidin-4-ones 9 were synthetised. These compounds reduced with iron(II) hydroxide gave 6-amino-2-aryl-1,2-dihydro-3H-pyrido[2,3-d]pyrimidin-4-ones 10 as expected.     

Quantum-chemical study of possible structural transformations in 3-methylthio-3-phenyl-2-propenethial

The plausible formation of 3-methylthio-1-phenyl-2-propene-1-thione and 3-methylthio-3-phenyl-2-propenethial in the reaction of 3-methylthio-3-phenyl-2-propene-1-N,N-dimethyliminium iodide with hydrogen sulfide was shown in the framework of semiempirical AM1 and PM3 methods. In polar media, these products can be trimerized into four types of structures. The kind of trimer depends on the shift of the equilibrium in the 3-methylthio-3-phenyl-2-propenethial ⇄ 3-methylthio-1-phenyl-2-propene-1-thione mixture. Each of the four types of trimers is characterized by the presence of three nearly planar sixmembered pseudo-chelate rings. The possibility of obtaining derivatives of 1,2-dithiolane (the basic fragment of lipoic acid) from the reaction products in nonpolar solvents was considered. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1273–1277, July, 1997.     

Substituted N-cyanomethyl-2-halo-N-methylarenecarboxamides as precursors of 1,4-benzothiazepines

2-Halogeno substituted N-cyanomethyl-N-methylbenzamides 1a-1i were investigated in a correlation analysis by ir spectroscopy to determine the conformational behavior. Compound 1h gives 4-methyl-2-methylthio-8-nitro-5-oxo-4,5-dihydro-1,4-benzothiazepine-3-carbonitrile 3 by dithiocarboxylation procedure whereas 1b was not able to react to heterocyclic seven-membered ring system.     

Coordination compounds of copper(II) with substituted 3-{[(2-hydroxyphenyl)methylidene]amino}propane-1,2-diols

3-{[(2-Hydroxyphenyl)methylidene]amino}propane-1,2-diol, its 5-chloro-,5-bromo-, 5-nitro-, 3-methoxy derivatives, and 3-{[(2-hydroxynaphthyl-1)methylidene]amino}propane-1,2-diol react with hydrates of copper(II) chloride, bromide and nitrate in ethanol to form coordination compounds Cu(L)X·nH₂O. Template condensation reaction between 3-aminopropane-1,2-diol and 2,3-, 2,4- or 2,5-dihydroxybenzaldehyde in the presence of copper(II) nitrate trihydrate results in similar compounds Cu(L)NO₃·nH₂O. Structure of some of the condensation products was identified by X-ray analysis. Thermolysis of the substances obtained occurs through the dehydration step (70–90°C) and complete thermal decomposition (290–560°C).     

METHYLTHIODITHIOLYLIUM REACTIONS WITH 2-BUTENE NITRILES DERIVATIVES

Abstract

The 3-methylthio-1. 2-dithiolylium including at 5 position a donor substituent, in acetic acid in the presence of pyridine, the 2-methylthio-1. 3-dithiolylium ions in methylene chloride-triethylamine, react with the 2-butene nitrile derivatives and lead to the (A) and (B) corresponding 4-dithiolylidene-2-butene nitriles. In contrast ring opening reaction of the 1, 2-dithiole is observed when 2-cyano-3-phenyl-2-butene nitrile reacts with the 3-methylthio-4-aryl-1. 2-dithiolylium ions in 3 and 5 positions, in methylene chloride-triethylamine. The nucleophilic attack on the 5 position of the dithiolylium ion leads to a 2-cyano-3-phenyl-3 (4-aryl-5-methylthio-2-thienyl) propene nitrile (C), meanwhile the attack on the 3 position leads to a 2-cyano-3-phenyl-3-(4-aryl-3-mercapto-2-thienyl) propene nitrile (D). The proposed structures are established by means of physical methods (IR, NMR, and Mass Spectrometry) and by non ambiguous synthesis. The reactivities of the various sites are explained in function of the electronic and steric effects, furthermore the reaction conditions and the intermediary isolation allow to propose the mecanisms of these reactions.     

Studies on furan derivatives. XII. Nucleophilic substitution of methyl 5-nitro-2-furancarboxylate. Preparation of methyl 5-phenoxy-2-furancarboxylates

Twenty one methyl 5-phenoxy-2-furancarboxylates prepared from the reaction of methyl 5-nitro-2-furan-carboxylate with phenoxides via displacement of the nitro group. In the reaction of potassium 2-nitrophen-oxide with methyl 5-nitro-2-furancarboxylate at 110°-120°, 2,2′-dinitrodiphenyl ether was obtained as a main product.     

Synthesis of 1-aryl-3-trifluoromethyl-5-methylthio-1,2,4-triazoles from 2-arylmethylisothiosemicarbazides and 1,1,1-trichloro-3,3,3-trifluoroacetone

The reaction of 1,1,1-trichloro-3,3,3-trifluoroacetone with S-methyl-2-arylisothiosemicarbazides affords an unusual synthesis of 1-aryl-3-trifluoromethyl-5-methylthio-1,2,4-triazoles from which 1-aryl-3-trifluoromethyl-1,2,4(4H)-triazole-5-ones are obtained on treatment with base.     

Studies on furan derivatives. V. A novel ethoxycarbonylmethylation of the 5-nitro-2-furan ring in the reaction of α-(2-furyl)-β-(5-nitro-2-furyl)ethynyl with N-ethoxycarbonylmethylpyridinium ylide

An unexpected product, 1-(4-ethoxycarbonylmethyl-5-nitro-2-furyl)-2-(2-furyl)-3-ethoxycarbonyl-indolizine was obtained by the reaction of α-(2-furyl)-β-(5-nitro-2-furyl)ethynyl with N-ethoxy-carbonylmethylpyridinium ylide in N,N-dimethylformamide, together with 1-(5-nitro-2-furyl)-2-(2-furyl)-3-ethoxycarbonylindolizine.     

Thermal reactions of 2-(2-oxo-3-nitro-4-quinolinyl)malonates

Depending on the ester substituent, diethyl 2-(3-nitro-2-oxo-4-quinolinyl)malonates 2 give upon thermolysis ethyl 2-(3-nitro-2-oxo-4-quinolinyl)acetates 4, whereas dimethyl 2-(3-nitro-2-oxo-4-quinolinyl)-malonates 3 cyclize to give 1-methoxycarbonylisoxazolo[3,4-c]quinolin-4(5H)-ones 5. The necessary reaction conditions can be obtained easily with the help of differential scanning calorimetry.     

Synthesis of polyfunctionalized furans from 3-acetyl-1-aryl-2-pentene-1,4-diones

The BF₃-catalyzed cyclization of 3-acetyl-1-aryl-2-pentene-1,4-diones 1a-e in the presence of water in boiling tetrahydrofuran gave bis(3-acetyl-5-aryl-2-furyl)methanes 2a-e in 26-79% yields along with a small amount of 3-acetyl-5-aryl-2-methylfurans 3a-e. The exact structure of 2a was determined by X-ray crystallography. The use of a half volume of the solvent for the reaction of 1a resulted in the formation of 2,4-bis(3-acetyl-5-phenyl-2-furfuryl)-3-acetyl-5-phenylfuran (4) together with 2a and 3a. A similar reaction of 1a was carried out in the presence of 3-acetyl-5-(4-methylphenyl)-2-methylfuran (3d) to afford 4-(3-acetyl-5-phenyl-2-furfuryl)-3-acetyl-5-(4-methylphenyl)-2-methylfuran (5) in 49% yield. The BF₃-catalyzed reaction of 1a with 2,4-pentanedione in dry tetrahydrofuran at 23°C gave 3-(3-acetyl-5-phenyl-2-furfuryl)-4-hydroxy-3-penten-2-one (6a) and 3-(3-acetyl-2-methyl-4-phenyl-5-furyl)-4-hydroxy-3-penten-2-one (7a) in 66 and 24% yields, respectively. The product distribution depended on the reaction temperature. A similar reaction of 1b-e also yielded the corresponding trisubstituted furans 6b-e and tetrasubstituted furans 7b-e in good yields. These results suggested the presence of the furfuryl carbocation intermediate A during the reaction. The one-pot synthesis of 6a and 7a was also achieved by a similar reaction using phenylglyoxal. The deoxygenation of 1a with triphenylphosphine gave 3a in 88% yield, while 1a was treated with concentrated hydrochloric acid to yield 3-acetyl-2-chloromethyl-5-phenylfuran (8) which was quantitatively transformed in ethanol into 3-acetyl-2-ethoxymethyl-5-phenylfuran (9) and in water into 3-acetyl-5-phenylfurfuryl alcohol (10), respectively. In addition, the Diels-Alder reaction of cyclopantadiene with 1a gave the corresponding [4+2] cycloaddition products 11 and 12.     

Formation and Crystal Structure of the Salt (IC(PPh3)2)2I[I3]·(I2)2 with a new Polyiodide Chain

The reaction of the carbodiphosphorane Ph₃P=C=PPh₃ ( 1 ) with MeI in the presence of iodine gives the oxidation product (IC(PPh₃)₂)₂I[I₃]·(I₂)₂ ( 2 ). In the solid state dimeric units linked by indefinite ···I^?···I₂···I₃^?···I₂···I^?··· chains are found. An additional I···I contact between the cation and the I₂ molecule is formed, amounting to 359.23(5) pm. 2 crystallizes in the monoclinic space group P2/c, with the unit cell dimensions a = 2053.9(1), b = 1011.4(1), c = 1889.8(1) pm; β = 105.21(1)° and Z = 4.     

1-氯-3-硝基-2-丁烯与2-硝基丙烷钠盐的SRN1反应

本文研究了1-氯-3-硝基-2-丁烯与2-硝基丙烷钠盐的SRN1反应, 结果表明这种开链状纯脂肪族烯丙基型化合物发生了不重排的SRN1反应.     

1-偶氮苯-3-(3-硝基-5-氯-2-吡啶)三氮烯的合成及其与镍(Ⅱ)离子的显色反应

合成了新显色剂1-偶氮苯-3-(3-硝基-5-氯-2-吡啶)三氮烯(ABNCPDT),并研究了它与镍的显色反应.在pH 10.5的Na2B4O7-NaOH缓冲溶液中,TX-100表面活性剂存在下,试剂与镍生成4∶1型红色配合物.配合物的最大吸收峰位于540 nm,表观摩尔吸光系数为1.86×105L.mol-1.cm-1.N i2+浓度在0~480μg/L范围内符合比尔定律.用拟定方法测定铝合金中微量镍,结果满意.     

2-甲硫基-7(5)-取代-3-吡唑并[1,5-a]嘧啶甲酸乙酯的区域选择性合成与2D NMR 研究

利用3-甲硫基-4-乙氧羰基-5-氨基-1H-吡唑分别与甲基/芳基烯胺酮反应, 合成了8种新的化合物2-甲硫基-7-取代-3-吡唑并[1,5-a]嘧啶甲酸乙酯(3a～3g)和2-甲硫基-5-甲基-3-吡唑并[1,5-a]嘧啶甲酸乙酯(4a). 化合物的结构均经元素分析, IR, ¹H NMR, MS所证实, 异构体3a和4a的结构进一步由¹³C NMR, HMQC和HMBC确认. 同时, 探讨了区域选择性合成吡唑并[1,5-a]嘧啶类化合物可能的反应机理, 并对部分化合物杀菌活性进行了测试.     

On the reaction between alkyl isocyanides and 3-benzylidene-2,4-pentanedione. A convenient synthetic route to densely functionalized furans

Summary Alkyl isocyanides undergo a formal [1+4] cycloaddition reaction with 3-benzylidene-2,4-pentanedione yielding multiply functionalized furan ring systems in fairly high yields. The¹H NMR spectrum of 4-acetyl-2-(N-benzylamino)-5-methyl-3-phenylfuran shows an AB pattern for the benzylic methylene protons as a result of a restricted rotation about the bond between the acetyl group and the furan ring, thus giving rise to perpendicular disymmetric planes.

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Eine einfache Synthese von hochfunktionalisierten Furanen durch Reaktion von Alkylisocyaniden mit 3-Benzyliden-2,4-pentadion

Zusammenfassung Alkylisocyanide gehen mit 3-Benzyliden-2,4-pentadion eine formale [1+4]-Cycloaddition ein, die in relativ hohen Ausbeuten zu mehrfach funktionalisierten Furansystemen führt. Das¹H-NMR-Spektrum von 4-Acetyl-2-(N-benzylamino)-5-methyl-3-phenylfuran zeigt für die benzylischen Methylenprotonen ein AB-System, da das Molekül durch die sterische Hinderung der Rotation der Acetylgruppe asymmetrisch wird.

     

1,2,4-triazines. 1. A convenient synthesis of 4,5-dihydro-1,2,4-triazin-3-(2H)one and its 6-substituted derivatives

A facile synthesis of 4,5-dihydro-1,2,4-triazin-3-(2H)one (2a) from 5-methylthio-1,2,4-triazin-3-(2H)one (1a) with sodium borohydride is described. The reaction provides a convenient method for its 6-substituted derivatives (2b-h).     

Unusual reaction of 5-benzoyl-3-ethoxycarbonyl-6-methylthio-1-r-1,2-dihydropyridin-2-ones with nitrogen-containing 1,4-dinucleophiles

The reaction of 5-benzoyl-3-ethoxycarbonyl-6-methylthio-1-R-1,2-dihydropyridin-2-ones with the nitrogen-containing 1,4-dinucleophiles o-phenylenediamine, o-aminothiophenol, and ethylenediamine, proceeds as a recyclization, the products of which are derivatives of 5-(1H-benzimidazol-2-yl)-2H-2-pyranone, 5-(benzothiazol-2-yl)-2H-2-pyranone, and 5-(4,5-dihydro-1H-imidazol-2-yl)-2H-2-pyra-none respectively. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1089–1095, July, 2008.     

Komplexchemie P-reicher Phosphane und Silylphosphane. III. Die Komplexverbindungen (t-Bu)3P9 · Cr(CO)5 und (t-Bu)3P9 · 2 Cr(CO)5 des Nonaphosphans(3), (t-Bu)3P9

Transition Metal Complexes of P-rich Phosphanes and Silyphosphanes. III. Complex Compounds (t-Bu)₃P₉ · Cr(CO)₅ and (t-Bu)₃P₉ · 2 Cr(CO)₅ Derived from Nonaphosphane (3) (t-Bu)₃P₉ The reaction of (t-Bu)₃P₉ 1 with Cr(CO)₅ · THF in a molar ratio of 1:1 yields (t-Bu)₃P₉ · Cr(CO)₅ 2 (yellow crystals) with the Cr(CO)₅ group coordinated to an equatorial P atom of the P₉ skeleton. In the reaction of 1 with 2 moles of Cr(CO)₅ · THF the complex product (t-Bu)₃P₉ · 2 Cr(CO)₅ 3 is formed with the second Cr(CO)₅ group linked to a basal P atom. Evidence for this comes from ³¹P NMR spectra as well as from crystal structure determinations of 2 and 3.2 crystallizes in the space group P2₁/n with a = 1012,9(2) pm, b = 2961,9(4) pm, c = 983,2(2) pm, β = 101,41(2)° and Z = 4 formula units. 3 crystallizes on the space group Pbcn with a = 2675,8(8) pm, b = 1222,4(2)pm, c = 2212,3 pm and Z = 8. In 2 and 3 the equatorial P atoms opposite to the P₂ dumbbell are complexed. The further complexation in 3 takes place at a basal P atom in Z-arrangement. The distances d(P Cr) are 243.5(1) pm and 240.5(1) pm and 240.5(1) pm for the equatorial P atoms in bf 2 and 3, respectively. For the basal P atom is 3 the distance in 235.7 pm. The P P distance range from 217.5 to 223.0 pm with the shorter ones at the bridgehead atom and the longer one at the P₂ dumbbell. The structures are discussed with that of the free ligand.