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Catalytic production of high-energy-density spiro polycyclic jet fuel with biomass derivatives
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作者 Wen-Jing Zhang Yan-Cheng Hu +3 位作者 Yan-Hong Tan Jia Li Ning Li Jing-Pei Cao 《Journal of Energy Chemistry》 2025年第2期760-768,I0016,共10页
High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combu... High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combustion heat can provide more propulsion energy.To reduce the reliance on petroleum source,it is highly desirable to develop renewable alternatives for the production of strained polycyclic HED fuel,but which remains a big challenge because of the inaccessibility caused by the high strain,We herein demonstrate a three-step catalytic route towards highly strained C_(17)and C_(18)spirofuel with biomass feedstocks.The process includes catalytic aldol condensation of renewable cyclohexanone/cyclopentanone with benzaldehyde,catalytic spiro Diels-Alder(D-A)reaction of aldol adduct with isoprene,and catalytic hydrodeoxygenation.The key spiro D-A reaction is enabled by the catalysis of heterogeneous Lewis acidic ionic liquid.The chloroaluminate IL,formed by benign urea and AICl3,exhibits good catalytic performance and reusability for this step.An eventual hydrodeoxygenation(HDO)over Pd/C and H-Y produces strained tricyclic spirofuel with density>0.93 g/mL,combustion heat>41 MJ/L and freezing point<-40℃,which are better than the properties of tactical fuel RJ-4.Therefore,it is anticipated that the as-prepared renewable fuels have the potential to replace traditional petroleum-derived HED fuels. 展开更多
关键词 Biomass derivatives High-energy-density spiro polycyclic fuel Cycloaddition Lewis acidic ionic liquid
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trans-4'a-Methyl-3',4'a,9',10',10'a-hexahydro-spiro[cyclobutane-1,1'(2H)-phenanthrene]的全合成
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作者 戴伟昊 霍晨雨 +2 位作者 郑天禄 朱道勇 王少华 《有机化学》 CSCD 北大核心 2024年第11期3386-3391,共6页
以苯丙醛为起始原料,通过两种策略的使用完成trans-4'a-methyl-3',4'a,9',10',10'a-hexahydro-spiro[cyclobutane-1,1'(2H)-phenanthrene]的首次全合成.具体的关键步骤分别为金催化的1,3-酰基迁移/串联环化... 以苯丙醛为起始原料,通过两种策略的使用完成trans-4'a-methyl-3',4'a,9',10',10'a-hexahydro-spiro[cyclobutane-1,1'(2H)-phenanthrene]的首次全合成.具体的关键步骤分别为金催化的1,3-酰基迁移/串联环化和InI3催化的多烯环化. 展开更多
关键词 trans-4'a-methyl-3' 4'a 9' 10' 10'a-hexahydro-spiro[cyclobutane-1 1'(2H)-phenanthrene] 全合成 天然产物
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ZnO/Spiro-MeOTAD异质结自驱动光电探测器的制备及性能(特邀)
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作者 李朋凡 黄雨欣 +4 位作者 俞学伟 冯仕亮 姜岩峰 闫大为 于平平 《光子学报》 EI CAS CSCD 北大核心 2024年第7期58-67,共10页
ZnO具有高稳定性、低成本、宽带隙等优点,被广泛用于光电探测器但响应速度较慢,采用Zn(TFSI)2和CNT∶TiO_(2)作为混合掺杂剂来代替Li-TFSI,以提高Spiro-MeOTAD的稳定性及光电性能,采用旋涂法制备了ZnO/Spiro-MeOTAD异质结构筑光电探测器... ZnO具有高稳定性、低成本、宽带隙等优点,被广泛用于光电探测器但响应速度较慢,采用Zn(TFSI)2和CNT∶TiO_(2)作为混合掺杂剂来代替Li-TFSI,以提高Spiro-MeOTAD的稳定性及光电性能,采用旋涂法制备了ZnO/Spiro-MeOTAD异质结构筑光电探测器。ZnO/Spiro-MeOTAD光电探测器在250~600 nm波长范围内,具有良好的自驱动特性。在0 V条件下,ZnO/Spiro-MeOTAD器件在368 nm的入射光照射下具有最高的光电性能,响应度为27.34 mA W^(-1),比探测率为3.62×10^(11)Jones,开关比为2029,上升/下降时间分别为0.71 s/0.55 s,相较于ZnO的光电性能(响应度为17.74 mA·W^(-1),比探测率为5.11×10^(10)Jones,开关比为63.6,上升/下降时间为11.76 s/1.49 s)分别提升提高了1.5倍、7倍、32倍。ZnO/Spiro-MeOTAD器件在550 nm处仍具有明显响应,响应度和比探测率分别为2.48 mA·W^(-1)和3.32×10^(10)Jones,对比ZnO器件提高了248倍和940倍。不同放置时间(1个月)和预处理温度(0~140℃)下光电流的变化,验证了Spiro-MeOTAD加入构筑p-n异质结,不仅可以显著提升ZnO基光电探测器的响应度、开关比和响应速度,同时使得探测器具有良好的稳定性,可以应用于较高温度工作环境。 展开更多
关键词 光电探测器 异质结 旋涂法 ZNO spiro-MeOTAD 自驱动
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以Spiro-OMeTAD作为空穴传输层的ZnS/SnS太阳能电池模拟研究
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作者 唐华著 肖清泉 +1 位作者 付莎莎 谢泉 《人工晶体学报》 CAS 北大核心 2024年第8期1394-1408,共15页
硫化亚锡(SnS)因其合适的电学和光学特性而被作为太阳能电池的吸收层进行研究。Spiro-OMeTAD常用作空穴传输层以提高太阳能电池性能。本文采用wxAMPS软件对SnS基太阳能电池ZnS/SnS/Spiro-OMeTAD进行模拟研究。主要研究分析Spiro-OMeTAD... 硫化亚锡(SnS)因其合适的电学和光学特性而被作为太阳能电池的吸收层进行研究。Spiro-OMeTAD常用作空穴传输层以提高太阳能电池性能。本文采用wxAMPS软件对SnS基太阳能电池ZnS/SnS/Spiro-OMeTAD进行模拟研究。主要研究分析Spiro-OMeTAD空穴传输层对太阳能电池性能的影响,其中包括:开路电压、短路电流密度、填充因子、光电转换效率及量子效率。研究结果表明:在加入Spiro-OMeTAD空穴传输层后,ZnS/SnS/Spiro-OMeTAD太阳能电池的开路电压(V_(OC))增加至0.958 V,短路电流(J_(SC))增加到32.96 mA/cm^(2),填充因子(FF)和光电转换效率(PCE)分别达到了79.26%和25.07%,电池性能取决于电池各层厚度、掺杂浓度、缺陷态密度及工作温度。通过研究表明Spiro-OMeTAD作为空穴传输层,有利于提高太阳能电池的各性能,并且ZnS/SnS/Spiro-OMeTAD是一种十分具有发展潜力的光伏器件结构。 展开更多
关键词 硫化亚锡 硫化锌 spiro-OMeTAD 空穴传输层 异质结太阳能电池 wxAMPS 缺陷
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Spiro-tiger康复训练对青少年运动性哮喘中长跑运动员肺功能与气道修复的影响
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作者 马骁 《体育科技文献通报》 2024年第3期272-274,共3页
目的:探讨Spiro-tiger康复训练对青少年运动性哮喘中长跑运动员的肺功能和气道修复的影响。观察对照组和实验组进行的不同康复训练过程,结果发现:①Spiro-tiger康复训练在气道重塑、肺功能和血气指标方面表现出显著的优势。②观察组在9... 目的:探讨Spiro-tiger康复训练对青少年运动性哮喘中长跑运动员的肺功能和气道修复的影响。观察对照组和实验组进行的不同康复训练过程,结果发现:①Spiro-tiger康复训练在气道重塑、肺功能和血气指标方面表现出显著的优势。②观察组在9周的Spiro-tiger康复训练后,气道炎症介质水平显著下降,肺功能指标显著提高,血气指标也呈现有益的改善。③相较于传统康复训练,Spiro-tiger康复训练对于提高青少年运动性哮喘中长跑运动员的气道健康和肺功能更为有效。据此建议:教练将Spiro-tiger康复训练作为青少年运动性哮喘康复的首选方法,并制定个性化的康复计划以满足患者的不同需求。 展开更多
关键词 spiro-tiger康复训练 中长跑 肺功能
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Spirotryprostatin类生物碱的合成研究进展 被引量:4
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作者 马养民 范超 《有机化学》 SCIE CAS CSCD 北大核心 2016年第10期2380-2396,共17页
Spirotryprostatin类生物碱是一类具有螺环吲哚二酮哌嗪结构的生物碱,其结构特点是吲哚部分和二酮哌嗪部分通过一个螺碳原子手性中心相连.由于具有这样特殊的结构使得螺环吲哚二酮哌嗪化合物具有一些生理和药理活性,尤其对细胞周期有较... Spirotryprostatin类生物碱是一类具有螺环吲哚二酮哌嗪结构的生物碱,其结构特点是吲哚部分和二酮哌嗪部分通过一个螺碳原子手性中心相连.由于具有这样特殊的结构使得螺环吲哚二酮哌嗪化合物具有一些生理和药理活性,尤其对细胞周期有较好的抑制活性.近年来,spirotryprostatin类生物碱的合成得到了广泛的研究,根据其结构中螺环手性中心形成的方法不同,对spirotryprostatin类生物碱的全合成研究进展进行综述. 展开更多
关键词 spirotryprostatin 螺环吲哚二酮哌嗪 生物碱 生物活性 全合成
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Syntheses and Crystal Structures of Two Novel Spiro Compounds Containing 1,5-Dioxaspiro[5.5]undecane-2,4-dione 被引量:3
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作者 曾伍兰 孟庆国 +2 位作者 郭焕美 张磊 建方方 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期696-699,共4页
Two novel spiro compounds,3-benzylidene-1,5-dioxaspiro[5.5]undecane-2,4-dione 1 and 3-(2-fluorobenzylidene)-1,5-dioxaspiro[5.5]undecane-2,4-dione 2,have been synthesized and characterized by X-ray single-crystal dif... Two novel spiro compounds,3-benzylidene-1,5-dioxaspiro[5.5]undecane-2,4-dione 1 and 3-(2-fluorobenzylidene)-1,5-dioxaspiro[5.5]undecane-2,4-dione 2,have been synthesized and characterized by X-ray single-crystal diffraction,IR and elemental analysis.Compound 1 belongs to the monoclinic system,space group P21/n with a=12.326(3),b=5.6420(11),c=20.089(4),β= 101.79(3)o,C16H16O4,Mr= 272.29,V=1367.7(5)3,Z=4,Dc=1.322g/cm3,F(000)=576,μ(MoKa)=0.095 mm-1,the final R=0.0420 and wR=0.1159.Compound 2 is of monoclinic system,space group P21/n with a=12.283(3),b=5.6367(11),c=20.055(4),β=102.00(3)o,C16H15FO4,Mr=290.28,V=1358.2(5)3,Z=4,Dc=1.420 g/cm3,F(000)=608,μ(MoKa)=0.110 mm-1,the final R=0.0353 and wR=0.0860. 展开更多
关键词 synthesis crystal structure 1 5-dioxaspiro[5.5]undecane-2 4-dione spiro compounds
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基于Spiro-tiger训练仪的肺康复对COPD稳定期患者呼吸力学、气道重塑的影响 被引量:4
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作者 丁洁 向文海 +4 位作者 王启星 龚秀玲 杨扬 王桂丽 肖伟 《中国医学物理学杂志》 CSCD 2023年第12期1558-1563,共6页
目的:探讨慢性阻塞性肺疾病(COPD)稳定期患者采用基于Spiro-tiger训练仪的肺康复对呼吸力学、气道重塑的影响。方法:选取在上海瑞金医院南翔分院就诊的93例COPD稳定期患者,通过随机数表法分为对照组(46例)与观察组(47例)进行研究,对照... 目的:探讨慢性阻塞性肺疾病(COPD)稳定期患者采用基于Spiro-tiger训练仪的肺康复对呼吸力学、气道重塑的影响。方法:选取在上海瑞金医院南翔分院就诊的93例COPD稳定期患者,通过随机数表法分为对照组(46例)与观察组(47例)进行研究,对照组采用缩唇-腹式呼吸操干预,观察组在对照组基础上采用Spiro-tiger训练仪干预,两组均连续干预9周,对比两组干预前、干预9周后呼吸力学(呼吸频率、潮气量、每分通气量、呼吸道压力峰值)、气道重塑[基质金属蛋白酶-9(MMP-9)、血管内皮生长因子(VEGF)、转化生长因子(TGF-β1)]、肺功能[用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、FEV1/FVC]、血气指标[动脉血氧分压(PaO_(2))、动脉血二氧化碳分压(PaCO_(2))]、6 min步行距离、健康状况[Borg分级及圣乔治呼吸问卷(SGRQ)评分],并随访6个月,统计COPD急性加重发生状况。结果:干预9周,相较于对照组,观察组的呼吸频率、呼吸道压力峰值低,潮气量高(P<0.05);两组每分通气量比较差异无统计学意义(P>0.05);相较于对照组,观察组的MMP-9、VEGF、TGF-β1、PaCO_(2)水平低,FVC、FEV1、FEV1/FVC、PaO_(2)水平高(P<0.05);相较于对照组,观察组的6 min步行距离长,Borg分级评分、SGRQ评分低于干预前,且观察组变化幅度大于对照组(P<0.05);随访6个月,观察组COPD急性加重发生率(4.26%)低于对照组(19.57%)(P<0.05)。结论:基于Spiro-tiger训练仪的肺康复可有效改善COPD稳定期患者呼吸力学、肺功能、血气指标及健康状况,减轻气道重塑,减少COPD急性加重。 展开更多
关键词 慢性阻塞性肺疾病 spiro-tiger训练仪 呼吸力学 气道重塑
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Design,synthesis and insecticidal activity of spiro heterocycle containing neonicotinoid analogs 被引量:5
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作者 Nan-Yang Chen Li-Ping Ren +4 位作者 Min-Ming Zou Zhi-Ping Xu Xu-Sheng Shao Xiao-Yong Xu Zhong Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第2期197-200,共4页
Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenon... Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenone framework were designed and synthesized. Insecticidal evaluation showed that some of spirobenzofuranone containing neonicotinoids exhibited moderate activity against cowpea aphid, armyworm or brown planthopper. 展开更多
关键词 NEONICOTINOID spiro heterocycle Activity INSECTICIDE
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DNA Modification with Photochromic Spiro Compounds 被引量:2
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作者 PengZHANG TeruoMatsuura 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期299-302,共4页
The photochromic spiropyrans and spirooxazine having a succinimidyl ester or isothiocyanate pendant group can form covalent products with transaminated DNA. The absorption spectra and solid reflection spectra of modi... The photochromic spiropyrans and spirooxazine having a succinimidyl ester or isothiocyanate pendant group can form covalent products with transaminated DNA. The absorption spectra and solid reflection spectra of modified DNA with these photochromic spiro compounds were investigated. 展开更多
关键词 Photochromic spiro compound MODIFICATION DNA.
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Highly enantioselective construction of CF_(3) -bearing all-carbon quaternary stereocenters: Chiral spiro-fused bisoxazoline ligands with 1,1'-binaphthyl sidearm for asymmetric Michael-type Friedel-Crafts reaction 被引量:2
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作者 Robert Li-Yuan Bao Lei Shi Kang Fu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第5期2415-2419,共5页
A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared.The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Craft... A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared.The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Crafts reaction, affording the products bearing a trifluoromethylated all-carbon quaternary stereocenter with moderate to excellent yields(up to 99%) and good to excellent enantioselectivies(up to> 99.9% ee). Moreover, a proposed model of chiral pocket revealed that the attack of indole from the Re-face of β-CF_(3)-β-disubstituted nitroalkene was favorable. 展开更多
关键词 Chiral bisoxazoline ligand Chiral pocket Chiral spiro ligand Friedel-Crafts reaction Trifluoromethylated all-carbon quaternary stereocenter
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Synthesis and Photochromic Properties of Azido Analogues of Spiropyran and Spirooxazine as Nucleic Acid Labeling Reagent 被引量:1
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作者 HuiGUO WuXinZOU QiJI JiBenMENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第6期751-754,共4页
A series of photo active azido analogues have been synthesized and their photochromic properties have also been investigated by UV-Vis spectrum. It will be used for the rapid and reliable preparation of large amounts ... A series of photo active azido analogues have been synthesized and their photochromic properties have also been investigated by UV-Vis spectrum. It will be used for the rapid and reliable preparation of large amounts of stable, non-radioactive labeled DNA and RNA hybridization probes. And it is supposed to be easily detected for its photochromic properties. 展开更多
关键词 Nucleic acid PHOTOCHROMIC label AZIDO spiro.
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H_4SiW_(12)O_(40):An efficient catalyst for the synthesis of new spiro-[dibenzo[a,i]xanthene- 14,3'-indoline]-2',8,13-triones 被引量:1
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作者 Li Min Yang Zhi Kui Yin Li Qiang Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第3期265-268,共4页
Novel spiro[dibenzo[a,i]xanthene-14,3'-indoline]-2',8,13-triones were prepared by the three-component reaction ofβ-naphthol, isatins,and 2-hydroxy-1,4-naphoquinone in the presence of a catalytic amount of H_4SiW_... Novel spiro[dibenzo[a,i]xanthene-14,3'-indoline]-2',8,13-triones were prepared by the three-component reaction ofβ-naphthol, isatins,and 2-hydroxy-1,4-naphoquinone in the presence of a catalytic amount of H_4SiW_(12)O_(40).This protocol provides a simple one-step procedure with the advantages of easy work-up,mild reaction conditions and environmentally benign. 展开更多
关键词 spiro[dibenzo[a i]xanthene-14 3'-indoline] Β-NAPHTHOL 2-Hydroxy-1 4-naphoquinone H_4SiW_(12)O_(40) Solvent-free
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Bio-distributions of [^(125)I]Spiro-I liposomes in mice
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作者 周鹤翔 陈瑞琴 +3 位作者 孙慧 张沛然 贾红梅 谢英 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第1期47-51,共5页
We investigated the bio-distributions of [125 I]Spiro-I formulated in sterically stabilized liposomes (SSL) or targeted liposomes (SSTL) in mice,especially their brain uptake.The [125 I]Spiro-I liposomes were prep... We investigated the bio-distributions of [125 I]Spiro-I formulated in sterically stabilized liposomes (SSL) or targeted liposomes (SSTL) in mice,especially their brain uptake.The [125 I]Spiro-I liposomes were prepared by film-ultrasound dispersion method.Cereport (RMP-7) was covalently conjugated with DSPE-PEG,which was attached to the surface of SSL to form SSTL.The encapsulation efficiencies (ee%) of [125 I]Spiro-I-SSL and [125 I]Spiro-I-SSTL were 97.47%±4.01% and 93.02%±2.98%,respectively.The average particle sizes were (66.47±0.76) nm and (71.40±0.45) nm,respectively.After intravenous administration,[125 I]Spiro-I was quickly eliminated from blood.SSL could prolong the retention time of [125 I]Spiro-I in blood and SSTL improved its brain uptake.The AUC of [125 I]Spiro-I-SSTL in brain was increased by 1.52 times as compared to [125 I]Spiro-I,indicating that SSTL could be used for the formulation of [125 I]Spiro-I for the imaging of central nervous system (CNS). 展开更多
关键词 [125I]spiro-I RMP-7 Liposome Bio-distribution
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1,3-Dipolar cycloaddition reaction for diastereoselective synthesis of functionalized dihydrospiro[indoline-3,2'-pyrroles] 被引量:1
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作者 Ping Wu Hong Gao +1 位作者 Jing Sun Chao-Guo Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期329-332,共4页
The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2'-pyrrol... The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2'-pyrroles]in moderate to good yields and with high diastereoselectivity.The reaction was accomplished by the tandem 1,3-dioplar cycloaddition of in situ generated azomethine ylide with acetylenedicarboxylate and the nucleophilic addition of pyrrole ring to second molecular acetylenedicarboxylate. 展开更多
关键词 One-pot reaction 1 3-Dipolar cycioaddition Azomethine ylide Electron-deficient alkyne spiro[indoline-3 2'-pyrrole]
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[bmim]OH: An efficient catalyst for the synthesis of mono and bis spirooxindole derivatives in ethanol at room temperature 被引量:3
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作者 Swapnil A. Padvi Yogesh A. Tayade +1 位作者 Yogesh B. Wagh Dipak S. Dalai 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第5期714-720,共7页
A rapid and efficient, one pot synthesis of spirooxindole derivatives has been attempted by three- component reaction of isatin, malononitrile and carbonyl compound possessing a reactive c^-methylene group by using ta... A rapid and efficient, one pot synthesis of spirooxindole derivatives has been attempted by three- component reaction of isatin, malononitrile and carbonyl compound possessing a reactive c^-methylene group by using task specific ionic liquid, 1-butyl-3-methyl imidazolium hydroxide [bmim]OH as a catalyst. The important features of this methodology are straight forward route in short reaction time at room temperature and avoid any hazardous organic solvent, toxic catalyst, tedious purification step. Interestingly, this protocol is not only limited to mono-systems but also to the synthesis of newer bis- spirooxindole system. The separation of the product and reusability of the catalyst are easy with excellent yield. The [bmim]OH catalyst system could be reused up to five recycles without appreciable loss of activity. 展开更多
关键词 Task specific ionic liquid [bmim]OH lsatin spiro compounds Green synthesis
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Ab Initio Study of the Mechanism of Forming a Spiro-Ge-heterocyclic Ring Compound Involving Si from Me_2Si=Ge: and Formaldehyde 被引量:2
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作者 卢秀慧 王党生 +1 位作者 李涛 廉贞霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第4期481-487,共7页
X2Si=Ge: (X = H, Me, F, CI, Br, Ph, Ar...) is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge: a... X2Si=Ge: (X = H, Me, F, CI, Br, Ph, Ar...) is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge: and formaldehyde has been investigated with the CCSD(T)//MP2/cc-pvtz method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants first form a four-membered Si-heterocyclic ring germylene through the [2+2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge: atom in the four-membered Si-heterocyclic ring germylene and the π orbital of formaldehyde form a π→p donor-acceptor bond, the four-membered Si-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge atom in the intermediate undergoes sp^3 hybridization after transition state, then the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound involving Si via a transition state. The research result indicates the laws of cycloaddition reaction between HzSi=Ge: and formaldehyde. It has important reference value for the cycloaddition reaction between X2Si=Ge: (X = H, Me, F, CI, Br, Ph, Ar…) and asymmetric to-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds involving Si. The study extends research area and enriches the research content of germylene chemistry. 展开更多
关键词 Me2Si=Ge: four-membered Si-heterocyclic ring germylene spiro-Ge-heterocyclicring compounds potential energy profile
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Theophylline as a new and green catalyst for the one-pot synthesis of spiro[benzo[α]pyrano[2,3-c]phenazine]and benzo[α]pyrano[2,3-c]phenazine derivatives under solvent-free conditions 被引量:1
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作者 Afshin Yazdani-Elah-Abadi Malek-Taher Maghsoodlou +1 位作者 Razieh Mohebat Reza Heydari 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期446-452,共7页
A green,convenient,high yielding and one-pot procedure for the synthesis of novel spiro[benzo[α]pyrano[2,3-c]phenazine]derivatives by domino multi-component condensation reaction between 2-hydroxynaphthalene-l,4-dion... A green,convenient,high yielding and one-pot procedure for the synthesis of novel spiro[benzo[α]pyrano[2,3-c]phenazine]derivatives by domino multi-component condensation reaction between 2-hydroxynaphthalene-l,4-dione,benzene-l,2-diamines,ninhydrine,and malononitrile in the presence of a catalytic amount of 1,3-dimethyl-7H-purine-2,6-dione(theophylline) as an expedient,eco-friendly and reusable solid base catalyst under thermal,microwave irradiation and solvent-free conditions.This procedure has also been applied successfully for the synthesis of benzo[α]pyrano[2,3-c]phenazines. 展开更多
关键词 Multi-component domino reactions(MDRs) Green chemistry Theophylline spiro[benzo[α]pyrano[2 3-c]phenazine] Benzo[α]pyrano[2 3-c]phenazine
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Chiral Separation of Spiro-compounds and Determination Configuration 被引量:1
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作者 LIANG Ya GUO Jing-jing LIU Xiu-ming WEI Rong-bao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第4期441-444,共4页
Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synth... Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synthesizing active enantiomers, or as surface modifiers on silica particles to resolve entantiomers. In this study, five spiro compounds of 3,9-diphenyl-2,4,8,10-tetraoxaspiro[5.5]-undecane(1), 3,9-(4-methoxyphenyl)-2,4,8,10-tetraoxaspiro [5.5] -undecane(2), 3,9-(4-methylphenyl)-2,4,8,10-tetraoxaspiro [5.5] -undecane(3), 4,4'-(2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diyl)dibenzoic acid(4) and 3,9-di(4-formyl-phenyl)-2,4,8,10-tetraoxa-spiro[5.5]-undecane(5) were synthesized by grinding pentaerythritol with benzaldehyde, 4-methoxybenzaldehyde, 4-methylbenzaldehyde, 4-carboxybenzaldehyde or terephthalaldehyde monoacetal in the presence of InI3r3 under solvent-free conditions. A normal phase HPLC method was successfully developed to resolve entantiomers of compounds 1--5 on a chiral column. Specific optical rotation of R or S entantiomers(1) was determined and the corresponding configurations were proposed based on Lowe's rule. 展开更多
关键词 Chiral separation spiro-COMPOUNDS Optical rotation
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Synthesis of Some New Spiro <i>β</i>-Lactams and Thiazolidinones Compounds Containing Sulfur Incorporating Quinon Compounds 被引量:1
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作者 Nadia Ali Ahmed Elkanzi 《International Journal of Organic Chemistry》 2012年第4期352-361,共10页
A series of spiro, β-Lactams, and thiazolidinones incorporating compounds 4 have been synthesized by cycloaddition reaction of, chloroacetyl chloride and mercaptoacetic acid with the synthesized Shiff,s bases 5a-c to... A series of spiro, β-Lactams, and thiazolidinones incorporating compounds 4 have been synthesized by cycloaddition reaction of, chloroacetyl chloride and mercaptoacetic acid with the synthesized Shiff,s bases 5a-c to give new spiro β- Lactam 6a-c and spiro thiazolidinone 7a-c the cycloaddition were characterized by spectral data including HNMR, 13C-NMR, IR and elemental analysis. 展开更多
关键词 Β-LACTAM spiro THIAZOLIDINONE Synthesized Cycloaddition
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