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The night-time atmospheric chemistry of the biogenic volatile organic compounds (Z)-hex-4-en-1-ol, (Z)-hex-3-en-1-ol ('leaf alcohol'), (E)-hex-3-en-1-ol, (Z)-hex-2-en-1-ol and (E)-hex-2-en-1-ol, has been studied at room temperature. Rate coefficients for reactions of the nitrate radical (NO(3)) with these stress-induced plant emissions were measured using the discharge-flow technique. We employed off-axis continuous-wave cavity-enhanced absorption spectroscopy (CEAS) for the detection of NO(3), which enabled us to work in excess of the hexenol compounds over NO(3). The rate coefficients determined were (2.93 +/- 0.58) x 10(-13) cm(3) molecule(-1) s(-1), (2.67 +/- 0.42) x 10(-13) cm(3) molecule(-1) s(-1), (4.43 +/- 0.91) x 10(-13) cm(3) molecule(-1) s(-1), (1.56 +/- 0.24) x 10(-13) cm(3) molecule(-1) s(-1), and (1.30 +/- 0.24) x 10(-13) cm(3) molecule(-1) s(-1) for (Z)-hex-4-en-1-ol, (Z)-hex-3-en-1-ol, (E)-hex-3-en-1-ol, (Z)-hex-2-en-1-ol and (E)-hex-2-en-1-ol. The rate coefficient for the reaction of NO(3) with (Z)-hex-3-en-1-ol agrees with the single published determination of the rate coefficient using a relative method. The other rate coefficients have not been measured before and are compared to estimated values. Relative-rate studies were also performed, but required modification of the standard technique because N(2)O(5) (used as the source of NO(3)) itself reacts with the hexenols. We used varying excesses of NO(2) to determine simultaneously rate coefficients for reactions of NO(3) and N(2)O(5) with (E)-hex-3-en-1-ol of (5.2 +/- 1.8) x 10(-13) cm(3) molecule(-1) s(-1) and (3.1 +/- 2.3) x 10(-18) cm(3) molecule(-1) s(-1). Our new determinations suggest atmospheric lifetimes with respect to NO(3)-initiated oxidation of roughly 1-4 h for the hexenols, comparable with lifetimes estimated for the atmospheric degradation by OH and shorter lifetimes than for attack by O(3). Recent measurements of [N(2)O(5)] suggest that the gas-phase reactions of N(2)O(5) with unsaturated alcohols will not be of importance under usual atmospheric conditions, but they certainly can be in laboratory systems when determining rate coefficients.  相似文献   

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M.N. Patil 《Tetrahedron letters》2010,51(45):5927-5929
Both the diastereomers of (±)-3-amino-2,2-dimethyl-1,3-diphenylpropan-1-ol were synthesized starting from a common intermediate, namely, β-hydroxy oxime 6. Diastereoselective reduction with NaBH4/TiCl4 and H2-Pd/C provided syn- and anti-isomers, respectively. Good overall yield and selectivity were realized using a simple protocol.  相似文献   

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The X-ray diffraction analysis of 2,2-di(phenyl-4-ol)propane dimethacrylate, 2,2-di(phenyl-4-ol)propane diacrylate, pyrocatechol diacrylate, and hydroquinone diacrylate has shown that oligomer molecules within crystals are packed in stacks, where (meth)acrylate fragments of neighboring molecules are parallel to each other. The minimum distances between the centers of double bonds C=C of (meth)acrylate fragments in 2,2-di(phenyl-4-ol)propane dimethacrylate, 2,2-di(phenyl-4-ol)propane diacrylate, pyrocatechol diacrylate, and hydroquinone diacrylate are 4.208, 4.012, 3.621, and 3.739 describing the reduced rate of photopolymerization of molten monomers (with 9,10-phenanthrenequinone used as a photoinitiator) versus conversion show maxima at degrees of polymerization of 8, 16, 22, and 38%; the limiting conversions are 29, 36, 44, and 86%, respectively. The maximum reduced rates of photopolymerization of 2,2-di(phenyl-4-ol)propane dimethacrylate and diacrylate are nearly the same, whereas the rates of photopolymerization of hydroquinone diacrylate and pyrocatechol diacrylate are higher by a factor of 4 than those of the corresponding dimethacrylates.  相似文献   

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A method has been developed for obtaining (Z)tetradec-11-en-1-ol and (Z)-hexadec-11-en-1-ol via dodec-11-yn-1-ol.A. N. Nesmeyanov Institute of Organometallic Compounds, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 776–779, November–December, 1984.  相似文献   

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A method has been developed for obtaining (Z)tetradec-11-en-1-ol and (Z)-hexadec-11-en-1-ol via dodec-11-yn-1-ol.  相似文献   

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The reactions of arenediazonium tetrafluoroborates with 3-(allyloxy)propane-1,2-diol and 2,2-bis(allyloxymethyl)butan-1-ol in the presence of the thiocyanate nucleophile were used to obtain 3-(3-aryl-2-thiocyanatopropoxy)propane-1,2-diols and 2-[(allyloxy)methyl]-2-[(3-aryl-2-thiocyanatopropoxy)methyl]-butan-1-ols. Irrespective of reagent ratio, the second allyl fragment of 2,2-bis(allyloxymethyl)butan-1-ol fails to enter thiocyanatarylation. The presence of hydroxy groups in the unsaturated compounds studied render the latter less reactive than allyl derivatives containing no such groups.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 2019–2022.Original Russian Text Copyright © 2004 by Grishchuk, Baranovskii, Kovalskii, Gorbovoi.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

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2,2-diphenyl-1-(trifluoromethanesulphonyl)-hydrazyl was prepared by oxidation of the corresponding hydrazine, and is stable in solution. Its ESR spectrum is interpreted in terms of a larger coupling constant for the tricoordinated than for the dicoordinated nitrogen, and of proton coupling constants indicating non-equivalent phenyl groups.  相似文献   

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取代苯甲醛经缩合、催化氢化、环氧化和开环反应合成了9种2,2-二甲基-5-取代苯基-3-(1,2,4-三唑-1-基甲基)-3-戊醇类化合物和2种2,2-二甲基-5-取代苯基-3-(1,2,4-三唑-4-基甲基)-3-戊醇类新化合物. 并对1,2,4-三唑-1-基衍生物和1,2,4-三唑-4-基衍生物的选择性合成进行了研究; 新化合物结构经质谱, 1H NMR, 元素分析等确证, 并用单晶X射线衍射测定了化合物1a的晶体结构. 生物活性测试结果表明, 部分化合物具有强杀菌活性.  相似文献   

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The catalytic reaction of 1-ethynylcyclohexan-1-ol (EC) in the presence of bisphosphine nickel(II) complexes yields a linear trimer. The trimer could be isolated and characterized by means of MS, IR and NMR spectroscopies. The reaction mechanism is also discussed.  相似文献   

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