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1.
以新型水溶性二磺化 - 1-苯基二苯并膦 (简称 PDBPDS)为配体 ,制备了铑膦配合物 Rh(acac) (CO ) -(PDBPDS) 3.将其负载于高吸水性载体上 ,制得负载水相催化剂 ,并对催化剂的制备条件进行了优化 .以人造沸石为载体 ,在载水量 30 % ,[Rh]=2 .0× 10 - 5、 [P]/ [Rh]=40的条件下 ,筛选出丙烯氢甲酰化反应的最佳工艺条件 .在反应温度 10 0℃、压力 2 .0 MPa、搅拌速度为 5 0 0 r/ m in条件下 ,催化剂活性达 10 12 g丁醛 / (g Rh· h) ;正异比高达 43.5 ;在有机相中铑的浓度为 1.2× 10 - 9,解决了均相反应催化剂回收和循环使用的问题 .实验结果表明 ,新型配体二磺化 - 1-苯基二苯并膦是一性能较好的新配体 ,所制备的新型负载水相催化剂是一有较好开发前景的新型催化剂 相似文献
2.
用量子化学 AMI方法优化了 1 -苯基二苯并膦二磺化产物 ( PDBPDS)和三磺化三苯基膦 ( TPPTS)的几何构型 .比较两种化合物的空间结构和电子结构发现 ,在氢甲酰化铑膦催化反应体系中 ,PDBPDS的配体性能优于 TPPTS.首次研究了以 PDBPDS为配体的铑膦催化剂对丙烯氢甲酰化反应的催化性能 ,考察了反应温度、压力、膦铑物质的量比和搅拌速度对催化活性和选择性的影响 .结果表明 ,在 2 .0 MPa,1 0 0℃ ,膦铑物质的量比为 35 ,搅拌速度为 5 0 0 r/min及 V( H2 ) /V( CO) =1 /1的条件下 ,催化活性可达到 2 80 0 g(丁醛 ) /[g(铑 )·h],正异构产物物质的量比为 1 2 .3,在相同条件下与传统的三磺化三苯基膦 ( TPPTS)为配体的铑膦催化剂相比 ,催化活性和选择性提高了 2倍 .反应结束后 ,有机相和水相分离简单 ,有机相铑浓度仅为3.6× 1 0 - 8mol/L,有效地解决了铑流失问题 ,表明 PDBPDS是极具开发前景的新型水溶性配体 相似文献
3.
基于非离子表面活性膦配体的临界溶解温度特性 ,研究了以 Rh Cl3· 3H2 O为催化剂前体、聚氧乙烯基取代膦为配体原位合成的膦铑配合物催化剂 ,对有机单相体系中苯乙烯氢甲酰化反应的催化性能 .考察了反应温度、压力及不同聚氧乙烯基取代膦 -铑配合物催化剂对反应的影响 .以 Rh/PETPP配合物为催化剂时 ,在 T=10 0℃ ,p=6 .0 MPa (CO/H2 =1∶ 1)条件下 ,反应 3.5 h后 ,烯烃转化率和产物醛收率可分别达 96 .7%和 92 .6 % 相似文献
4.
依据量子化学理论计算 ,设计并优化了 1-苯基二苯并膦 (1- phenydibenzophosphole,简称 PDBP)磺化制备二磺化 1-苯基二苯并膦 (5 H- phenyl- 3,13- disulfonatodibenophosphole,简称 PDBPDS)的工艺 ,重点探讨了 SO3/PDBP比、反应温度、反应时间以及硼膦比对磺化产物收率的影响 .实验结果表明 ,采用 5 0 %发烟硫酸作磺化剂、SO3/ PDBP摩尔比为 3,H3BO3/ PDBP比为 5 ,在 13~ 15℃及无水无氧条件下反应 5 0 h,磺化产物收率可达 85 % .此外 ,还将所得产物用作丙烯氢甲酰化两相反应催化剂的配体 ,大大提高了催化剂的活性和产物正异比 ,且有机相中铑含量仅为 3.6× 10 - 8,有效地控制了铑流失 .实验结果证明了新型水溶性配体 PDBPDS是一个能实现均相反应多相化的、很有开发前景的配体 . 相似文献
5.
以乙酰丙酮羰基铑为催化剂母体,以水溶性三苯基膦三间磺酸钠(TPPTS)为配体,在超临界CO2和水复合溶剂中成功地实现了超临界条件下的均相丙烯氢甲酰化反应. 最佳反应条件为: 温度55 ℃,铑的浓度15 μg/ml, P/Rh摩尔比18. 在压力为12.0~14.0 MPa下反应6 h后,产物正丁醛/异丁醛摩尔比可达4.3~4.5,丁醛的时空收率达190.1~205.3 g/(g·h). 反应过程中体系处于超临界状态,反应结束后分为水、油两相,铑催化剂溶于水相,产物处于油相,油相中铑的含量仅为1.0 ng/ml,基本上消除了铑的流失,实现了催化剂与产物的有效分离,便于催化剂的回收和循环使用. 与相同反应条件下的水-有机两相氢甲酰化反应相比,超临界CO2和水复合溶剂中的丙烯氢甲酰化反应具有更高的反应速率和产物正异比. 相似文献
6.
用量子化学AM1方法优化了1-苯基二苯并膦(PDBP)和三苯基膦(TPP)的几何构型,比较了两种化合物的电子结构和空间结构,发现PDBP作为羧基合成铑膦催化剂的配体要优于三苯基膦(TPP);系统研究了PDBP的合成方法,其最佳合成条件为:在无水无氧的条件下,采用二乙胺锂与溴化四苯基膦摩尔比为3,反应温度为22℃,反应5h,反应后酸化,pH值为1-2,产物收率可达到85%-88%,采用元素分析、红外、核磁等方法,对其结果进行了表征,并将PDBP用于丙烯氢甲酰化反应的催化剂配体。实验证明,在相同的反应条件下,以其为配体的催化剂活性约是目前工业上使用的以三苯基膦为配体的催化剂的1.2倍,选择性约为其1.7倍。 相似文献
7.
以4,4'-二羟基二苯丙烷和2,4-二叔丁基苯酚为原料合成了一种新型双膦亚磷酸酯配体,并用此配体和Rh(acac)(CO)2原位形成的催化体系催化1-己烯的氢甲酰化反应.系统考察了反应温度、压力、P/Rh和溶剂四种反应参数对催化体系的催化性能影响.选择了最佳的反应条件,在铑浓度为0.75×10-3mol/L、P/Rh比为10、温度100℃、压力(H2/CO=1)2.0MPa的条件下反应1.0h,在溶剂甲苯中1-己烯的转化率可达到100%,醛选择性为98.7%,TOF为3498.6h-1.在相同的条件下与以三苯基膦和单膦亚磷酸三(2,4-二叔丁基苯基)酯为配体的铑催化剂相比较,以新型双膦亚磷酸酯为配体的铑催化剂的催化活性是PPh3的1.6倍,而与亚磷酸三(2,4-二叔丁基苯基)酯的催化活性相当. 相似文献
8.
以SiO2为载体,制备了负载型水相铑膦催化剂。在反应温度为100-110℃,合成气CO:H2=1:1,反应压力2.0MPa,「Rh」=7.5×10^5,P/Rh=25的条件下,进行丙烯氢甲酰化反应。结果表明,时空收率可达194-228g丁醛,正异比高达约14.2,反应结束后催化剂与体系易分离,铑在有机相中的浓度仅为1×10^-9-4×10^-9,基本消除了铑的流失,克服了均相反应中催化剂铑的回收和 相似文献
9.
以溶胶-凝胶与锚链固定相结合的方法制备了新型多相化羰基铑膦配合物催化剂.利用FT-IR,XPS和ICP对催化剂进行了表征.考察了该催化剂对1-己烯氢甲酰化反应的催化性能,得到较佳的反应条件,即反应温度100℃、反应时间12h、催化剂用量为0.3382g(相当于金属铑含量为4.4×10-5mol)、反应压力5.0MPa.此时1-己烯的转化率为98.5%、醛的选择性92.4%、n/i比1.43.该催化剂循环使用7次仍具有较高的催化活性和选择性,表明该催化剂具有好的循环使用性能.XPS、ICP分析证明铑的部分流失主要是由于氢甲酰化反条件下CO取代膦配体所致. 相似文献
10.
将合成的三 (3,4-二甲氧基苯基) 膦 (TDMOPP) 用作 Rh 催化剂配体, 并用于 1-十二烯氢甲酰化反应, 考察了膦/铑比和反应温度对 Rh-TDMOPP 催化剂活性和选择性的影响. 结果表明, 在膦/铑比与反应温度较低时, Rh-TDMOPP 活性是 Rh-三苯基膦催化剂的 3 倍. 相似文献
11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。 相似文献
13.
The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness. 相似文献
14.
Two vanilloids, (5 E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one ( 1) and 4-[3-hydroxydecyl]-2-methoxyphenol ( 2), isolated from the dried seeds of Grains of Paradise ( Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared. 相似文献
15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992. 相似文献
16.
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。 相似文献
17.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite ( P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time ( th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with ( th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with ( th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700 oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides
and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques.
Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated.
Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997. 相似文献
20.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。 相似文献
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