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The influence of each condition on the reaction speed and yield was studied, and the optimal conditions were: the ratio of the amount of substance of aromatic amine and heptafluoro-isopropyl iodine was 1:1.1~1.5, the amount of substance of sodium dithionite, sodium bicarbonate, aniline compounds were respectively 1.1~1.3, the amount of substance of phase transfer catalyst TBAB and aniline compounds was 0.05~0.1, the concentration of aniline compound was 0.5~1.0 mol/L, reaction temperature was 10~20 ℃, and the solvent was aether.

最佳结果为:芳胺与七氟异丙基碘的物质的量比1:1.1~1.5,连二亚硫酸钠、碳酸氢钠与苯胺的物质的量分别为1.1~1.3,相转移催化剂四丁基溴化铵与苯胺的物质的量比在0.05~0.1,溶剂总用量使苯胺浓度在0.5~1.0 mol/L;反应温度10~20℃;溶剂采用乙醚。取代基供电子性越强,反应时间越短,产率越高;氨基的对位优先反应,氨基的邻位较难发生反应;且七氟异丙基总是优先取代在芳环电子云密度较高的位置上。

When the radical center is located at the bridge methyl group, ring expansion is the favored rearrangement pathway unless a radical-stabilizing substituent is placed in the cyclobutyl ring adjacent to the bridge methyl group.

当自由基中心位于双环的桥甲基时,扩环过程占主导地位,但是与桥甲基相邻的环丁基上存在能够稳定自由基的取代基时,重排以开环为主。

Bulky and electron-rich MOP-type phosphine ligand 2-ditertbutylphosphino-2'-isopropyloxy- 1,1'-binaphthyl (L1) shows good catalytic activity in palladium-catalyzed α-arylation of 1,3-dicarbonyl compounds.

富电子、大位阻MOP型烷基膦配体2-二叔丁基膦-2'-异丙氧基-1,1'-联萘(L1)在钯催化的1,3-二羰基化合物的α-芳基化反应中显示了较好的催化活性。

Bulky and electron-rich MOP-type phosphine ligand 2-ditertbutylphosphino-2 -isopropyloxy 1,1 -binaphthyl (L1) shows good catalytic activity in palladium-catalyzed α-arylation of 1,3-dicarbony compounds.

富电子、大位阻MOP型烷基膦配体2-二叔丁基膦-2'-异丙氧基-1,1'-联萘(L1)在钯催化的1,3-二羰基化合物的α-芳基化反应中显示了较好的催化活性。

Studing on samarium diiodide promoted asymmetric intramolecular reducing coupling reactions, we have made the resolution of the racemic biaryl dials by using enantiomeric N-tert-butanesulfinamine as the resolving reagent successfully and thus obtained a series of axially chiral biaryl dials with high enantiomeric excess.

中文摘要在二碘化钐促进的分子内不对称还原偶联反应中,我们不仅对联芳基二醛底物的合成路线进行了优化,还发现N-叔丁基亚磺酰胺辅基可以作为手性试剂,成功地对联芳基骨架二醛化合物进行拆分,得到高对映体过量的轴手性二醛类化合物。

This article reports a new kind of copolymer, non polar polar terpolymer : poly(styrene-butadiene-methyl methacrylate ) P(S-b-B-b-MMA prepared by anionic polymerization with n BuLi as initiator, 1,1 diphenylethylene as capping agent and lithium 2-(-methoxyethoxy) ethoxide as complex agent.

以正丁基锂为引发剂, 1 ,1-二苯基乙烯为戴帽剂, 2-(2-甲氧基乙氧基)乙氧基锂为络合剂,在环己烷、四氢呋喃混合溶剂中,采用阴离子聚合法,于-70℃~-40℃合成了非极性-极性的三嵌段共聚物聚苯乙烯-聚丁二烯-聚甲基丙烯酸甲酯,并借用GPC、1H-NMR、DSC、TEM、IR等仪器对共聚物进行了表征。

In previous results, Alkyl substituted propargylic dithioacetals treating with butyl lithium then were allowed to react with carbonyl compounds to form homopropargylic alcohol with high yields and highly regioselective.

在本实验室先前的研究中发现,烷基取代炔丙基硫缩酮与正丁基锂进行开环反应后,若是与羰基化合物反应,能够以高产率、具位向选择性的生成高炔丙基醇。

A kind of silica loaded cerium dioxide particles was prepared by the sol-gel method and the heat-resist performance of the silica loaded cerium dioxide particle added silicon rubber materials improved evidently as compared with that of the purely silica added materials.

研究了两种硅烷偶联剂——乙烯基三乙氧基硅烷(A-151)和乙烯基三特丁基过氧硅烷对高硬度硅橡胶性能的影响,比较发现A-151不但可以显著改善高硬度硅橡胶的回弹性,而且使用方便、成本较低。

The conductivity and the molar conductivity of the ionic liquid in actone, water, DMF, acetic acid were investigated at different temperatures.

利用磷酸三丁酯与N-甲基咪唑在恒温150℃下一步合成了离子液体1-丁基-3-甲基咪唑磷酸二丁酯,考察了其在丙酮,水,DMF,乙酸溶剂中的电导率及摩尔电导率。

Have carried on testing service for nearly 200 hazardous substances, including Asbestos, PAHs, Phthalates, NP/NPEO, AZO, CFC/HCFC/Halons, PVC, PCB, PCT, PCN, CP, Mirex, TPT/TBT/TBTO, Formaldehyde, Heavy metals, can help your products in fully compliance with 'green purchase' request of international buyers.

开展除RoHS以外的近200种有害物质检测业务,包括石棉、多环芳烃、邻苯二甲酸盐、壬基苯酚/壬基苯酚乙氧基化合物、偶氮染料、氟氯烷烃/氢氯氟烷烃/海龙、聚氯乙烯、多氯联苯、多氯三联苯、多氯化萘、短链氯化石蜡、灭蚊灵、三苯基锡类/三丁基锡类/二的氧化物、甲醛、重金属等,涉及范围完全满足各国际买家的&绿色采购&要求。

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We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称;三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起,称之为挽歌体诗人或者史诗诗人,他们被称为诗人,似乎只是因为遵守格律写作,而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。

This is not paper type of business,it's people business,with such huge money involved.

这不是纸上谈兵式的交易,这是人与人的业务,而且涉及金额巨大。