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51.
Kaiyu Liu Jinfeng Xu Shijun Liu Qiyuan Chen Zhongliang Xiao Daowu Yang 《Thermochimica Acta》2008,471(1-2):100-102
The excess molar enthalpies () for the binary mixtures of trimethyl phosphate (TMP) with alkanols {CH3(CH2)nOH, n = 0–3} have been measured with an isothermal calorimeter at 298.15 K and atmospheric pressure. The values are positive for all the mixtures over the whole composition range. The values increase in the order methanol < ethanol < 1-propanol < 1-butanol. The experimental results have been correlated with the Redlich–Kister equation. 相似文献
52.
Bo Wang Chuan Ming Yu Zhi Wei Chen Wei Ke Su 《中国化学快报》2008,19(8):904-906
A mild and simple method for the synthesis of dialkyl chlorophosphates is described, bis(trichloromethyl) carbonate (BTC) is used as the effective reagent for the conversion of dialkyl phosphites to their corresponding dialkyl chlorophosphates under mild conditions. 相似文献
53.
A phosphite ligand modified Rh/SiO2 catalyst has been developed for hydroformylation of internal olefins to linear aldehydes, which showed high activity and regioselectivity and could be separated easily by filtration after reaction in an autoclave. Effects of reaction temperature and syngas pressure on the performances of the catalyst in the reaction were also investigated. 相似文献
54.
Dr. Nilofar Baral Soniya Rani Pinku Saikia Dr. Pradip Maity 《European journal of organic chemistry》2023,26(4):e202201238
Organophosphites are nucleophilic in nature and can act as a good leaving group owing to the stability of the phosphite anion. This dual reactivity makes them good candidates for nucleophilic organocatalysis. However, phosphites were introduced only in 2004 as the umpolung catalyst for acylsilane substrates utilizing sequential Brook rearrangements. Very recently, phosphites have been reported to catalyze aza-rearrangements and radical reactions. In this review, we discuss the reactivity parameters to understand its lack of use, as well as the potential for catalysis. 相似文献
55.
The use of solution 17O NMR spectroscopy in verifying the mechanism of trialkyl phosphite hydrolysis is presented. Trimethyl phosphite was reacted with 17O-labeled H2O at different temperatures and two reactant concentrations, with the reaction being monitored by 17O NMR. Kinetic details elucidated from the NMR spectra are also discussed. 相似文献
56.
含苯并噻唑杂环的α-氨基膦酸二苯酯的合成及生物活性 总被引:8,自引:0,他引:8
α氨基膦酸作为氨基酸的含磷类似物,具有广泛的除草[1]、杀菌[2]和植物生长调节活性[3].最近的研究表明,某些α氨基膦酸衍生物还具有较好的抗植物病毒活性[4,5].在研究植物病毒抑制剂的过程中,我们发现含苯并噻唑杂环的α氨基膦酸二乙酯类化合物... 相似文献
57.
1,3,4—噻二唑的α—氨基膦酸酯衍生物的合成及其生物活性 总被引:7,自引:4,他引:3
利用2-氨基-5-烷基-1,3,4-噻二唑、芳笛醛和亚磷酸三苯酯泊类Mannich反应,合成了一系列1,3,4-噻二唑的α-氨基膦酸酯生物。它们的结构级元素分析、IR,HNMR和MS这。初步生物活性测试结果表明,目标化合物对5种病人有一定的抑制作用。 相似文献
58.
59.
Two open‐framework bimetallic phosphites, [C6H18N2][Co0.3Zn2.7 (HPO3)4] ( 1 ) and [C2H8N]2[Co0.3Zn2.7(HPO3)4] ( 2 ) were synthesized and characterized. The inorganic frameworks of the two compounds are constructed from strictly alternating MO4 (M = Zn, Co)tetrahedra and HPO3 pseudo pyramids, forming three‐dimensional networks with 8‐ring and 12‐ring channels for 1 and 16‐ring channels for 2 . The anionic frameworks of the two compounds can be easily transformed to a neutral framework structure with 16‐ring channels at room temperature. 相似文献
60.
Two three-dimensional open-framework zinc phosphites, H2aem·Zn3(HPO3)4·0.5H2O (1) and H2apm·Zn3(HPO3)4 (2), have been synthesized by a phosphorous acid flux method, where aem=4-(2-aminoethyl)morpholine and apm=4-(3-aminopropyl)morpholine. Compound 1 crystallizes in the monoclinic system, P21/c, a=9.5852(7) Å, b=20.3941(8) Å, c=10.5339(8) Å, β=94.125(9)°, V=2053.8(2) Å3, Z=4, R1=0.0319, wR2=0.0628. Compound 2 crystallizes in the monoclinic system, P21/n, a=8.589(2) Å, b=14.020(3) Å, c=16.606(3) Å, β=97.190(8)°, V=1983.9(7) Å3, Z=4, R1=0.0692, wR2=0.1479. Both compounds are based on (3,4)-connected networks with 8- and 12-ring channels, which are constructed from Zn3(HPO3)4 clusters as the same secondary building units. These inorganic clusters are spatially organized by different structure-directing agents into different three-dimensional frameworks. 相似文献