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1.
王敏  宋志国  姜恒  宫红 《有机化学》2008,28(9):1629-1632
室温无溶剂条件下, 乙酸能有效促进邻甲基苯磺酸铜催化一系列醇或酚和3,4-2H-二氢吡喃反应, 生成相应的四氢吡喃醚. 在乙酸存在条件下, 体系的催化性能有显著提高, 邻甲基苯磺酸铜用量仅需0.3 mol%(占醇或酚的摩尔分数)就能使反应在较短时间内完成. 反应结束后, 邻甲基苯磺酸铜经简单相分离可多次重复使用, 催化活性无明显下降. 产物结构经IR, 1H NMR, 元素分析进行表征.  相似文献   

2.
宋志国 《分子催化》2011,25(5):421-426
报道了硫酸钴-乙酸在室温、无溶剂条件下催化醇和酚的四氢吡喃化反应。硫酸钴-乙酸作为协同催化体系,二者缺一不可。与传统催化剂相比,新催化体系的催化活性最好.反应结束后,硫酸钴经简单相分离可回收,重复使用多次催化活性无明显下降。提出了可能的催化反应机理.  相似文献   

3.
徐亮  杨安卫  马宁 《有机化学》2013,(9):2004-2009
氧化石墨作为一种高效、低毒、易得、可重复使用的弱酸性催化剂用于醇和酚的四氢吡喃化保护与脱保护反应.反应在室温下短时间内即可完成,产物收率高,分子中的碳碳不饱和键不受影响,氧化石墨可重复使用至少4次.该方法具有操作简便、安全、经济、环境友好等优点.  相似文献   

4.
朱强  宫红  姜恒  王锐 《合成化学》2016,24(10):856-860
以过渡金属甲基磺酸盐[Mn(CH3SO3)2·2H2O, Cu(CH3SO3)2·4H2O, Co(CH3SO3)2·4H2O和Zn(CH3SO3)2·4H2O]为催化剂,在室温条件下催化醇的四氢吡喃化反应,并对反应条件进行了优化。结果表明:当醇用量为30 mmol,醇和3,4-二氢吡喃摩尔比为1.0 :1.1,甲基磺酸盐用量为1 mmol,二氯甲烷20 mL时,可高效催化醇的四氢吡喃化反应。与路易斯酸催化活性相比,过渡金属甲基磺酸盐催化醇的四氢吡喃化反应效果最好,催化酚的效果较差。用Mn(CH3SO3)2·2H2O和Cu(CH3SO3)2·4H2O催化正丁醇的四氢吡喃化反应,重复使用5次,收率分别为89%和92%。  相似文献   

5.
以浓硫酸改性的活性炭为催化剂,催化二氢吡喃对醇(酚)羟基的保护,使其形成相应的四氢吡喃醚(2):2在催化剂作用下能顺利的脱除保护基团.  相似文献   

6.
王锐 《化学研究》2009,20(2):79-82
用硅钨酸分别与硝酸铜、硝酸锌和硝酸铝采用复分解法合成了相应的硅钨酸盐.结合红外光谱、紫外光谱和热重等分析手段对这三种硅钨酸盐结构进行了表征,并考察了三种硅钨酸盐在醇的四氢毗喃化反应中的催化性能.结果表明:用0.7g具有Keggin结构的硅钨酸盐作催化剂,在室温无溶剂条件下,催化二氢吡喃(33mmol)与醇(30mmol)的反应,反应条件温和,工艺简单,催化效果好,无副产物生成.  相似文献   

7.
苯磺酸铜-乙酸催化醛的双乙酰化反应   总被引:1,自引:0,他引:1  
宫红  刘庆  姜恒 《合成化学》2008,16(2):176-179
苯磺酸铜-乙酸共催化体系于室温催化一系列醛的双乙酰化反应,合成了相应的1,1-二乙酸酯(2),产率59%~97%.2的结构经1H NMR和IR表征.  相似文献   

8.
以微乳化法制备的二氧化硅担载的的杂多酸催化剂Cu—H4SiW12O40在室温下能瞬间催化四氢吡喃化反应。且催化剂在至少重复使用四次而未见明显的失活。  相似文献   

9.
本文通过预先将醛和四氯化锡进行配位形成高活性的醛中间体,同时采用滴加高烯丙醇的方法高收率和高选择性地合成了2,4,6-三取代四氢吡喃.  相似文献   

10.
以1-Boc-3-氮杂环丁酮和甲基三苯基溴化磷为起始原料,经Wittig反应、加成环化、脱卤、羰基还原、成醚、哌嗪取代、苯甲酸甲酯衍生物取代、水解、磺胺缩合、脱Boc和四氢吡喃取代反应,合成了一个新型的含四元螺环胺四氢吡喃结构的磺胺类Venetoclax衍生物,总产率22%,其结构经1H NMR和HR-MS(ESI)表征。  相似文献   

11.
Abstract  Tetrahydropyranylation of alcohols and phenols was accomplished successfully using copper nitrate and acetic acid as a synergistic catalyst at room temperature under solvent-free condition. Compared with other synergistic catalytic systems, copper nitrate/acetic acid proved to be the most efficient. Both alcohols (primary, secondary, tertiary, benzylic, cyclic, allyl, cinnamyl, and furyl) and phenols reacted smoothly in high yields. Graphical abstract     相似文献   

12.
Copper p-toluenesulfonate/acetic acid was found to be an efficient, chemoselective synergistic catalytic system, with catalyst loading as low as 0.3 mol% leading to clean, high-yielding tetrahydropyranylation of a variety of alcohols and phenols. By simple phase-separation, copper p-toluenesulfonate can be easily recovered and reused for several times without deterioration in catalytic activity. Correspondence: Min Wang, College of Chemistry and Chemical Engineering, Bohai University, Jinzhou, China.  相似文献   

13.
A synergistic catalytic effect between copper methanesulfonate and acetic acid in tetrahydropyranylation of alcohols and phenol at room temperature under solvent free condition has been described. Both alcohols (primary, secondary and tertiary) and phenols reacted with 3,4-dihydro-2H-pyran smoothly to afford the corresponding tetrahydropyranyl ethers in good yields.  相似文献   

14.
Copper zirconium phosphate nanoparticles have been used as an efficient catalyst for the acetyla‐tion of a wide range of alcohols and phenols with acetic anhydride in good to excellent yields under sol...  相似文献   

15.
TAYEBEE Reza 《中国化学》2008,26(12):2273-2277
A simple, mild and effective procedure is reported to the generation of 2-tetrahydropyranyl acetals from alcohols. Keggin and Wells-Dawson heteropolyoxometalates were used as catalysts at ambient temperature in acetone as solvent with good yields and high selectivities in a short reaction time. Different reaction parameters affecting efficiency of the protocol were also studied. The use of these acid catalysts allows replacing the usual soluble inorganic acids, contributing to waste reduction.  相似文献   

16.
Titanium(IV) salophen trifluoromethanesulfonate, [TiIV(salophen)(OSO2CF3)2], as a catalyst enables selective tetrahydropyranylation of alcohols and phenols with 3,4‐dihydro‐2H‐pyran. Using this catalytic system, primary, secondary and tertiary alcohols, as well as phenols, were converted to their corresponding tetrahydropyranyl ethers in high yields and short reaction times at room temperature. Investigation of the chemoselectivity of this method showed discrimination between the activity of primary alcohols in the presence of secondary and tertiary alcohols and phenols. This heterogenized catalyst could be reused several times without loss of its catalytic activity. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

17.
孙培培  胡志新 《中国化学》2004,22(11):1341-1343
In dichloromethane, the nucleophilic addition of alcohols or phenols to 3,4-dihydro-2H-pyran (DHP) was catalyzed effectively by gallium triiodide which was generated in situ by the reaction of gallium metal and iodine to give the corresponding tetrahydropyranyl acetals in good to excellent yields.  相似文献   

18.
A simple and efficient tetrahydropyranylation of alcohols and phenols has been developed using NaHSO4-SiO2 (0.5 mol%) as a catalyst under solvent-free conditions to yield corresponding tetrahydropyranyl ethers in excellent yields.  相似文献   

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