Citation: Lin Chunhua, Yuan Jianjun, Liu Deyong, Zhang Houfu, Xu Zhaohui. Efficient Synthesis of 5, 5-(Phenylmethylene)bis(2, 2-dimethyl-1, 3-dioxane-4, 6-dione) Derivatives in Biobased Gluconic Acid Aqueous Solution[J]. Chinese Journal of Organic Chemistry, ;2017, 37(6): 1560-1564. doi: 10.6023/cjoc201612044 shu

Efficient Synthesis of 5, 5-(Phenylmethylene)bis(2, 2-dimethyl-1, 3-dioxane-4, 6-dione) Derivatives in Biobased Gluconic Acid Aqueous Solution

a.
Chemistry and Chemical Engineering Department, Jiangxi Normal University, Nanchang 330022
b.
Jiangxi Traditional Chinese Medecine Institute, Nanchang 330026

Corresponding author: Xu Zhaohui, gotoxzh@163.com
Received Date: 14 December 2016
Revised Date: 24 January 2017

Fund Project: the Graduate Innovation Foundation of Jiangxi Province YC2015-B023the National Science and Technology Project 2001BA323C

Figures(2)

Six kinds of 5, 5-(phenylmethylene)bis(2, 2-dimethyl-1, 3-dioxane-4, 6-dione) derivatives were synthesized by the reaction of aromatic aldehydes and 2, 2-dimethyl-1, 3-dioxane-4, 6-dione in biobased gluconic acid aqueous solution at 40 ℃. The reaction has the advantages of high yields (81%~92%), mild conditions, simple operation and environmental friendliness. Furthermore, GAAS can be reused for several times.
5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)属多羰基杂环衍生物, 分子内存酮-烯醇互变异构形式, 它具有优于曲酸和含羞草碱的络氨酸酶抑制性能^[1].它也是制备如三咪唑并嘧啶酮衍生物^[2]、氧杂恩二酮^[3]、吖啶环二酮^[4]及苯并吡喃^[5]等杂环化合物的重要中间体.因此, 5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)衍生物的合成研究一直令人注目.它通常由2, 2-二甲基-1, 3-二噁烷-4, 6-二酮与芳香醛在碱催化下反应而制得, 催化剂多为有机胺^[6]或无机碱^[7], 这些方法存在产品收率较低, 反应时间长、后处理复杂等不足.在极性溶剂中、无催化剂条件下制备5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)衍生物也有文献报道. Hedge等^[8]报道了无催化剂条件下在N, N-二甲基甲酰胺(DMF)或二甲基亚砜(DMSO)溶剂中合成5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮), 但后处理工艺复杂, 溶剂不易回收. Yu等^[9]报道了无催化剂条件下水相制备5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)的方法, 但反应副产物较多, 需柱层析分离产品, 因此发展绿色、简便和高效合成的新方法显得极为迫切.

以消除环境污染、提高反应效率和原子经济性、降低能耗为研究目的的绿色化学, 是化学重点发展方向之一^[10].葡萄糖酸溶液是一种绿色、对环境无污染的生物介质^[11], 通常为50%的水溶液, 并具有弱酸性, 已广泛用于多种有机反应, 如吲哚的Michael加成^[12]和苄醇与吲哚的Friedel-Crafts烷基化反应^[12], 二吲哚甲烷及其衍生物的合成^[13]、多组分反应合成螺环吲哚^[14]、Yonemitsu反应^[15]和多取代吡咯^[16].基于此, 笔者发展了以葡萄糖酸水溶液(GAAS)为反应介质和催化剂, 通过芳香醛和2, 2-二甲基-1, 3-二噁烷-4, 6-二酮(麦氏酸)的Knoevenagel缩合与Michael加成的串联反应合成5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)衍生物的简单、有效的方法.合成路线见Scheme 1.

图式1 化合物3a~3f和3g~3i的合成 Scheme1. Synthesis of 3a~3f and 3g~3i

图选项

下载全尺寸图像

下载幻灯片

1   结果与讨论

以苯甲醛和2, 2-二甲基-1, 3-二噁烷-4, 6-二酮为反应模型, 考察了无催化剂条件下无溶剂、不同溶剂、溶剂用量、反应时间和反应温度对反应的影响, 其结果见表 1.从表 1可以看出, 在无溶剂条件或常见有机溶剂如二氯甲烷、甲苯中都没有检测到化合物3a(表 1中Entries 1~3).溶剂的极性对反应有一定的影响, 此反应在DMSO非质子极性溶剂中的收率有显著提高(表 1中Entries 4), 但在极性质子溶剂中反应效果更佳(表 1中Entries 6~7).接着考察了乙酸水溶液、草酸水溶液、苹果酸水溶液、GAAS的催化效果, 其中GAAS的催化效果最佳(表 1中Entries 8~11).在室温下, 使用4.0 mL GAAS作溶剂反应4 h后, 化合物3a收率可达84%.升温至40 ℃反应, 反应时间明显缩短, 且收率提高显著, 达到89%, 而进一步升温度, 产品收率变化不大.为了优化葡萄糖酸溶液用量, 结果发现:当葡萄糖酸溶液用量为4.0 mL时效果最优.反应时间对产物收率影响也进行了考察, 结果表明:最佳反应时间为4 h.综上所述, 优化的反应条件是:在无催化剂条件下, 以GAAS (50%水溶液)为溶剂, GAAS用量4.0 mL, 反应原料(苯甲醛与2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)的物质的量之比为1:2, 反应温度为40 ℃, 最佳反应时间为4 h.

表 1 化合物3a的合成条件优化^a Table 1. Optimization of reaction conditions for the synthesis of compound 3a

表选项

导出Excel

下载全尺寸表图像

同时, 为了探讨GAAS水溶液对不同底物的普适性, 在上述优化反应条件下, 通过改变不同芳香醛与2, 2-二甲基-1, 3-二噁烷-4, 6-二酮进行Knoevenagel缩合与Michael加成的串联反应, 合成了6种5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)衍生物(3a~3f)(表 2).从表 2数据可看出, 以葡萄糖水溶液为溶剂和催化剂条件下, 该反应均可顺利进行, 并以81%~92%的较高收率得到相应的5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)衍生物.带吸电子基的芳香醛反应速度快于带供电子基的芳香醛, 对于带有强供电基团如4-甲氧基苯甲醛或4-N, N-二甲氨基苯甲醛仅能发生Knoevenagel缩合反应.此外, 苯甲醛上取代基的位置对产物收率有一定影响, 用邻硝基苯甲醛作底物时表现更明显, 由于空间位阻太大, 仅得到Knoevenagel缩合反应产物(3i), 而3-氯苯甲醛由于位阻明显小于邻硝基苯甲醛, 以92%收率得到目标产物.

表 2 化合物3a~3f和3g~3i的合成^a Table 2. Synthesis of 3a~3f and 3g~3i

表选项

导出Excel

下载全尺寸表图像

以苯甲醛和2, 2-二甲基-1, 3-二噁烷-4, 6-二酮为反应模型, 在优化的反应条件下反应结束后, 由于葡萄糖酸溶液为极性质子溶剂, 其与原料、产物均不互溶, 因此可以通过简单过滤回收葡萄糖酸溶液.回收后的葡萄糖酸溶液循环使用4次, 反应的收率依次为89%, 89%, 86%, 82%.

此外, 根据产物的结构和反应的特点, 参考文献[6, 13]的方法, 笔者以苯甲醛和2, 2-二甲基-1, 3-二噁烷-4, 6-二酮的反应为例说明Knoevenagel缩合与Michael加成的串联反应可能的反应机理.在反应过程中GAAS与原料的键合和离去起着非常重要的作用.生物介质GAAS通过与2, 2-二甲基-1, 3-二噁烷-4, 6-二酮形成氢键, 增强了2, 2-二甲基-1, 3-二噁烷-4, 6-二酮的互变异构体亚甲基碳的亲核性, 而芳香醛与GAAS形成氢键, 使醛羰基更易受亲核试剂的进攻, 发生Knoevenagel缩合反应生成中间体6, 再与2, 2-二甲基-1, 3-二噁烷-4, 6-二酮的互变异构体5发生Michael加成反应得目标产物3a.可能的反应过程, 如Scheme 2所示.

图式2 生成化合物3a可能的机理 Scheme2. Proposed mechanism for the imformation of 3a

图选项

下载全尺寸图像

下载幻灯片

2   结论

在无催化剂条件下, 以葡萄糖酸溶液为反应介质, 以不同芳香醛与2, 2-二甲基-1, 3-二噁烷-4, 6-二酮发生Knoevenagel缩合与Michael加成的串联反应, 有效合成了6种5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)衍生物, 并确定了较好的反应条件:当芳香醛与2, 2-二甲基-1, 3-二噁烷-4, 6-二酮的物质的量之比为1:2, 葡萄糖酸溶液用量为4.0 mL时, 40 ℃反应3.0~5.0 h, 产品收率为81%~92%.该反应具有反应温和、操作简单、环境友好及葡萄糖酸溶液能重复使用等优点.

3   实验部分

3.1   试剂与仪器

2, 2-二甲基-1, 3-二噁烷-4, 6-二酮按文献[17]制备; 苯甲醛、4-甲基苯甲醛、4-氯苯甲醛、4-氟苯甲醛、3-氯苯甲醛、4-硝基苯甲醛、2-硝基苯甲醛及4-甲氧基苯甲醛为分析纯; 其它均为化学纯.

瑞士BuchiB-540型显微熔点仪(温度计未经校正); 德国Bruker 400 MHz型核磁共振仪(DMSO-d₆为溶剂, TMS为内标); 日本岛津FT-IR-8400型红外仪(KBr压片); MS谱由ABI公司API3200三重四级杆质谱仪记录.

3.2   5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3a~3f)的合成

在20 mL试管中加入芳香醛(1 mmol)、2, 2-二甲基-1, 3-二噁烷-4, 6-二酮(2 mmol)和葡萄糖酸溶液(4.0 mL), 于40 ℃反应3.0~5.0 h, 反应完毕, 过滤, 滤液为葡萄糖酸溶液并用于下一次反应.滤饼用10 mL蒸馏水洗涤2次、无水乙醇重结晶、干燥得目标化合物3a~3i.

5, 5-(苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3a):白色固体, 熔点180~182 ℃ (lit.^[18] 180~182 ℃); ¹H NMR (400 MHz, CDCl₃) δ: 1.68 (s, 6H), 1.81 (s, 2H), 4.60~4.69 (m, 3H), 7.26~7.37 (m, 3H), 7.52~7.53 (m, 2H); ¹³C NMR (100 MHz, CDCl₃) δ: 26.59, 28.62, 40.02, 49.28, 105.41, 127.88, 128.38, 129.01, 140.57, 163.87, 165.21; ESI-MS m/z: 377.1 [M+H]⁺.

5, 5-(4-氟苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3b):白色固体, 熔点152~154 ℃; ¹H NMR (400 MHz, CDCl₃) δ: 1.71 (s, 6H), 1.82 (s, 2H), 4.59~4.66 (m, 3H), 7.00~7.06 (m, 2H), 7.51~7.55 (m, 2H); ¹³C NMR (400 MHz, CDCl₃) δ: 26.56, 28.59, 36.16, 49.31, 105.52, 114.12, 115.74, 128.08, 130.34, 164.54, 167.12; ESI-MS m/z: 395.1 [M+H]⁺.

5, 5-(4-氯苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3c):白色固体, 熔点161~163 ℃; ¹H NMR (400 MHz, CDCl₃) δ: 1.72 (s, 6H), 1.82 (s, 2H), 4.58~4.64 (m, 3H), 7.32 (d, J＝8.0 Hz, 2H), 7.49 (d, J＝8.0 Hz, 2H); ¹³C NMR (400 MHz, CDCl₃) δ: 26.56, 28.58, 39.36, 48.66, 105.54, 121.70, 127.40, 129.14, 129.98, 163.69, 165.48; ESI-MS m/z: 411.1 [M+H]⁺.

5, 5-(4-甲基苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3d):白色固体, 熔点148~150 ℃; ¹H NMR (400 MHz, CDCl₃) δ: 1.69 (s, 6H), 1.81 (s, 6H), 2.32 (s, 3H), 4.57~4.67 (m, 3H), 7.16 (d, J＝8.0 Hz, 2H), 7.42 (d, J＝8.0 Hz, 2H); ¹³C NMR (400 MHz, CDCl₃) δ: 21.07, 26.57, 28.63, 39.54, 49.37, 105.39, 128.25, 129.69, 134.26, 137.62, 163.97, 165.30; ESI-MS m/z: 391.1 [M+H]⁺.

5, 5-(4-硝基苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3e):白色固体, 熔点144~146 ℃; ¹H NMR (400 MHz, CDCl₃) δ: 1.75 (s, 6H), 1.83 (s, 6H), 4.71~4.74 (m, 3H), 6.75 (d, J＝12.0 Hz, 2H), 8.21 (d, J＝8.0 Hz, 2H); ¹³C NMR (400 MHz, CDCl₃) δ: 26.58, 28.50, 39.88, 48.79, 105.80, 124.13, 129.74, 135.66, 147.40, 163.64, 164.75; ESI-MS m/z: 422.1 [M+H]⁺.

5, 5-(3-氯苯基亚甲基)双(2, 2-二甲基-1, 3-二噁烷-4, 6-二酮)(3f):白色固体, 熔点152~154 ℃; ¹H NMR (400 MHz, CDCl₃) δ: 1.73 (s, 6H), 1.83 (s, 6H), 4.57~4.62 (m, 3H), 7.26~7.30 (m, 2H), 7.44~7.46 (m, 2H), 7.56 (s, 1H); ¹³C NMR (400 MHz, CDCl₃) δ: 26.61, 28.58, 39.65, 49.12, 105.57, 126.92, 128.16, 128.44, 130.23, 134.80, 142.78, 163.72, 165.04; ESI-MS m/z: 411.1 [M+H]⁺.

5-(4-甲氧苯基亚甲基)-2, 2-二甲基-1, 3-二噁烷-4, 6-二酮(3g):淡黄色固体, 熔点122~123 ℃ (lit.^[19] 126 ℃); ¹H NMR (400 MHz, CDCl₃) δ: 1.79 (s, 6H), 3.91 (s, 3H), 6.98 (d, J＝8.0 Hz, 2H), 8.23 (d, J＝8.0 Hz, 2H), 8.38 (s, 1H); ¹³C NMR (400 MHz, CDCl₃) δ: 27.53, 55.70, 104.18, 110.89, 114.39, 124.77, 137.66, 157.93, 160.49, 164.07, 164.67.

5-(4-N, N-二甲基苯基亚甲基)-2, 2-二甲基-1, 3-二噁烷-4, 6-二酮(3h):橙色固体, 熔点168~170 ℃ (lit.^[20] 166~168 ℃); ¹H NMR (400 MHz, CDCl₃) δ: 1.77 (s, 6H), 3.15 (s, 6H), 6.70 (d, J＝8.0 Hz, 2H), 8.25 (d, J＝8.0 Hz, 2H), 8.30 (s, 1H); ¹³C NMR (400 MHz, CDCl₃) δ: 27.33, 40.14, 103.45, 105.13, 111.33, 120.29, 138.94, 154.50, 158.05, 161.45, 165.22.

5-(2-硝基苯基亚甲基)-2, 2-二甲基-1, 3-二噁烷-4, 6-二酮(3i):淡黄色固体, 熔点119~120 ℃ (lit.^[21] 120~122 ℃); ¹H NMR (400 MHz, CDCl₃) δ: 1.82 (s, 6H), 7.50 (d, J＝7.7 Hz, 1H), 7.66 (t, J＝7.8, 1H), 7.75 (t, J＝7.6 Hz, 1H), 8.30 (d, J＝8.2 Hz, 1H), 8.80 (s, 1H); ¹³C NMR (400 MHz, CDCl₃) δ: 27.83, 105.48, 124.86, 130.32, 130.90, 133.82, 148.31, 155.80, 159.00, 161.53.

辅助材料(Supporting Information)  部分目标化合物3a, 3d, 3f的¹H NMR、¹³C NMR图谱.这些材料可以免费从本刊网站(http://sioc-journal.cn/)上下载.

References
1. [1]
  Khan, K. M.; Maharvi, G. M.; Khan, M. T.; Shaikh, A. J.; Bioorg. Med. Chem. 2006, 14, 344. doi: 10.1016/j.bmc.2005.08.029
2. [2]
  Lipson, V. V.; Orlov, V. D.; Desenko, S. M.; Karnozhitskaya, T. M.; Shirobokova, M. G. Chem. Heterocycl. Compd. 1999, 35, 595. doi: 10.1007/BF02324645
3. [3]
  Shanmugasundaram, P.; Prabahar, K. J.; Ramakrishnan, V. T. J. Heterocycl. Chem. 1993, 30, 1003. doi: 10.1002/jhet.v30:4
4. [4]
  Srividya, N.; Ramamurthy, P.; Shanmugasundaram, P.; Ramakrishnan, V. T. J. Org. Chem. 1996, 61, 5083. doi: 10.1021/jo9600316
5. [5]
  Marco, B. A.; Manuel, T. A.; Itzia, P. M.; Francisco, M. M.; Georgina, E. J. Chem. Crystallogr. 1999, 29, .
6. [6]
  Nader, N. P.; Ali, G.; Mohammad, B.; Alireza, S. Arabian J. Chem. 2013, 5, 1.
7. [7]
  Giancarlo, G.; Alberto, D.; Gian, M. N.; Giovanni, P.; Andrea, P.; Silvia, T. Eur. J. Org. Chem. 2003, 2003, 4438. doi: 10.1002/(ISSN)1099-0690
8. [8]
  Hedge, J. W.; Kruse, C. W.; Snyder, H. R. J. Org. Chem. 1961, 26, 992. doi: 10.1021/jo01063a002
9. [9]
  Yu, J. J.; Wang, L. M.; Liu, J. Q.; Guo, F. L.; Liu, Y.; Jiao, N. Green Chem. 2010, 12, 216. doi: 10.1039/B913816A
10. [10]
  Shi, D.-Q.; Ni, S.-N.; Dou, G.-L. Chin. J. Org. Chem. 2009, 29, 788 (in Chinese).
11. [11]
  Gu, Y. L.; Francois, J. Chem. Soc. Rev. 2013, 42, 9550. doi: 10.1039/c3cs60241a
12. [12]
  Zhou, B. H.; Yang, J.; Li, M. H.; Gu, Y. L. Green Chem. 2011, 13, 2204. doi: 10.1039/c1gc15411g
13. [13]
  Sheng, W.-L.; Du, Y.-Y.; Tian, F.-L.; Han, L.-M.; Zhu, N. Chem. Bull. 2012, 75, 1026 (in Chinese).
14. [14]
  Guo, R. Y.; Wang, P.; Wang, G. D.; Mo, L. P.; Zhang, Z.-H. Tetrahedron 2013, 69, 2056. doi: 10.1016/j.tet.2012.12.081
15. [15]
  Yan, N.; Xia, J.-H.; Xiong, Y.-K.; Xiong, B.; Lin, C. H.; Liao, W.-L. Chin. J. Org. Chem. 2014, 34, 2487 (in Chinese).
16. [16]
  Li, B. L.; Li, P. H.; Fang, X. Na.; Li, C. X.; Sun, J. L.; Mo, L. P.; Zhang, Z. H. Tetrahedron 2013, 69, 7011. doi: 10.1016/j.tet.2013.06.049
17. [17]
  Yan. N.; Xiong, B.; Liao, W.-L.; Xu, Z.-H. Chin. J. Org. Chem. 2010, 30, 1391 (in Chinese).
18. [18]
  Sajjad, S.; Malek, T. M.; Nourallah, H.; Mojtaba, L.; Santiago, G-G.; Laura, T-F. Chin. J. Catal. 2015, 36, 1023. doi: 10.1016/S1872-2067(15)60846-4
19. [19]
  Schuster, P.; Polansky, O. E.; Wessely, F. Monatsh. Chem. 1964, 95, 53. doi: 10.1007/BF00909251
20. [20]
  Xu, Z.-H; Yan, N.; Liao, W.-L. J. Jiangxi Normal Univ. (Nat. Sci.) 2012, 36, 524 (in Chinese). doi: 10.3969/j.issn.1000-5862.2012.05.021
21. [21]
  Le, W. J.; Lu, H. F.; Zhou, J. T.; Cheng, H. L.; Gao, Y. H. Tetrahedron Lett. 2013, 54, 5370. doi: 10.1016/j.tetlet.2013.07.116
1. [1]
  Khan, K. M.; Maharvi, G. M.; Khan, M. T.; Shaikh, A. J.; Bioorg. Med. Chem. 2006, 14, 344. doi: 10.1016/j.bmc.2005.08.029
2. [2]
  Lipson, V. V.; Orlov, V. D.; Desenko, S. M.; Karnozhitskaya, T. M.; Shirobokova, M. G. Chem. Heterocycl. Compd. 1999, 35, 595. doi: 10.1007/BF02324645
3. [3]
  Shanmugasundaram, P.; Prabahar, K. J.; Ramakrishnan, V. T. J. Heterocycl. Chem. 1993, 30, 1003. doi: 10.1002/jhet.v30:4
4. [4]
  Srividya, N.; Ramamurthy, P.; Shanmugasundaram, P.; Ramakrishnan, V. T. J. Org. Chem. 1996, 61, 5083. doi: 10.1021/jo9600316
5. [5]
  Marco, B. A.; Manuel, T. A.; Itzia, P. M.; Francisco, M. M.; Georgina, E. J. Chem. Crystallogr. 1999, 29, .
6. [6]
  Nader, N. P.; Ali, G.; Mohammad, B.; Alireza, S. Arabian J. Chem. 2013, 5, 1.
7. [7]
  Giancarlo, G.; Alberto, D.; Gian, M. N.; Giovanni, P.; Andrea, P.; Silvia, T. Eur. J. Org. Chem. 2003, 2003, 4438. doi: 10.1002/(ISSN)1099-0690
8. [8]
  Hedge, J. W.; Kruse, C. W.; Snyder, H. R. J. Org. Chem. 1961, 26, 992. doi: 10.1021/jo01063a002
9. [9]
  Yu, J. J.; Wang, L. M.; Liu, J. Q.; Guo, F. L.; Liu, Y.; Jiao, N. Green Chem. 2010, 12, 216. doi: 10.1039/B913816A
10. [10]
  Shi, D.-Q.; Ni, S.-N.; Dou, G.-L. Chin. J. Org. Chem. 2009, 29, 788 (in Chinese).
11. [11]
  Gu, Y. L.; Francois, J. Chem. Soc. Rev. 2013, 42, 9550. doi: 10.1039/c3cs60241a
12. [12]
  Zhou, B. H.; Yang, J.; Li, M. H.; Gu, Y. L. Green Chem. 2011, 13, 2204. doi: 10.1039/c1gc15411g
13. [13]
  Sheng, W.-L.; Du, Y.-Y.; Tian, F.-L.; Han, L.-M.; Zhu, N. Chem. Bull. 2012, 75, 1026 (in Chinese).
14. [14]
  Guo, R. Y.; Wang, P.; Wang, G. D.; Mo, L. P.; Zhang, Z.-H. Tetrahedron 2013, 69, 2056. doi: 10.1016/j.tet.2012.12.081
15. [15]
  Yan, N.; Xia, J.-H.; Xiong, Y.-K.; Xiong, B.; Lin, C. H.; Liao, W.-L. Chin. J. Org. Chem. 2014, 34, 2487 (in Chinese).
16. [16]
  Li, B. L.; Li, P. H.; Fang, X. Na.; Li, C. X.; Sun, J. L.; Mo, L. P.; Zhang, Z. H. Tetrahedron 2013, 69, 7011. doi: 10.1016/j.tet.2013.06.049
17. [17]
  Yan. N.; Xiong, B.; Liao, W.-L.; Xu, Z.-H. Chin. J. Org. Chem. 2010, 30, 1391 (in Chinese).
18. [18]
  Sajjad, S.; Malek, T. M.; Nourallah, H.; Mojtaba, L.; Santiago, G-G.; Laura, T-F. Chin. J. Catal. 2015, 36, 1023. doi: 10.1016/S1872-2067(15)60846-4
19. [19]
  Schuster, P.; Polansky, O. E.; Wessely, F. Monatsh. Chem. 1964, 95, 53. doi: 10.1007/BF00909251
20. [20]
  Xu, Z.-H; Yan, N.; Liao, W.-L. J. Jiangxi Normal Univ. (Nat. Sci.) 2012, 36, 524 (in Chinese). doi: 10.3969/j.issn.1000-5862.2012.05.021
21. [21]
  Le, W. J.; Lu, H. F.; Zhou, J. T.; Cheng, H. L.; Gao, Y. H. Tetrahedron Lett. 2013, 54, 5370. doi: 10.1016/j.tetlet.2013.07.116
1. [1]
  Zhuoming Liang , Ming Chen , Zhiwen Zheng , Kai Chen . Multidimensional Studies on Ketone-Enol Tautomerism of 1,3-Diketones By ¹H NMR. University Chemistry, 2024, 39(7): 361-367. doi: 10.3866/PKU.DXHX202311029
2. [2]
  Yinwu Su , Xuanwen Zheng , Jianghui Du , Boda Li , Tao Wang , Zhiyan Huang . Green Synthesis of 1,3-Dibromoacetone Using Halogen Exchange Method: Recommending a Basic Organic Synthesis Teaching Experiment. University Chemistry, 2024, 39(5): 307-314. doi: 10.3866/PKU.DXHX202311092
3. [3]
  Yongzhi LI , Han ZHANG , Gangding WANG , Yanwei SUI , Lei HOU , Yaoyu WANG . A two-dimensional metal-organic framework for the determination of nitrofurantoin and nitrofurazone in aqueous solution. Chinese Journal of Inorganic Chemistry, 2025, 41(2): 245-253. doi: 10.11862/CJIC.20240307
4. [4]
  Fan JIA , Wenbao XU , Fangbin LIU , Haihua ZHANG , Hongbing FU . Synthesis and electroluminescence properties of Mn²⁺ doped quasi-two-dimensional perovskites (PEA)₂Pb_yMn_1-yBr₄. Chinese Journal of Inorganic Chemistry, 2024, 40(6): 1114-1122. doi: 10.11862/CJIC.20230473
5. [5]
  Jun LUO , Baoshu LIU , Yunchang ZHANG , Bingkai WANG , Beibei GUO , Lan SHE , Tianheng CHEN . Europium(Ⅲ) metal-organic framework as a fluorescent probe for selectively and sensitively sensing Pb²⁺ in aqueous solution. Chinese Journal of Inorganic Chemistry, 2024, 40(12): 2438-2444. doi: 10.11862/CJIC.20240240
6. [6]
  Tingting Yu , Si Chen , Lianglong Sun , Tongtong Shi , Kai Sun , Xin Wang . Comprehensive Experimental Design for the Photochemical Synthesis, Analysis, and Characterization of Difluoropyrroles. University Chemistry, 2024, 39(11): 196-203. doi: 10.3866/PKU.DXHX202401022
7. [7]
  Liangzhen Hu , Li Ni , Ziyi Liu , Xiaohui Zhang , Bo Qin , Yan Xiong . A Green Chemistry Experiment on Electrochemical Synthesis of Benzophenone. University Chemistry, 2024, 39(6): 350-356. doi: 10.3866/PKU.DXHX202312001
8. [8]
  Yue Zhao , Yanfei Li , Tao Xiong . Copper Hydride-Catalyzed Nucleophilic Additions of Unsaturated Hydrocarbons to Aldehydes and Ketones. University Chemistry, 2024, 39(4): 280-285. doi: 10.3866/PKU.DXHX202309001
9. [9]
  Xiaoling LUO , Pintian ZOU , Xiaoyan WANG , Zheng LIU , Xiangfei KONG , Qun TANG , Sheng WANG . Synthesis, crystal structures, and properties of lanthanide metal-organic frameworks based on 2, 5-dibromoterephthalic acid ligand. Chinese Journal of Inorganic Chemistry, 2024, 40(6): 1143-1150. doi: 10.11862/CJIC.20230271
10. [10]
  Tianlong Zhang , Rongling Zhang , Hongsheng Tang , Yan Li , Hua Li . Online Monitoring and Mechanistic Analysis of 3,5-diamino-1,2,4-triazole (DAT) Synthesis via Raman Spectroscopy: A Recommendation for a Comprehensive Instrumental Analysis Experiment. University Chemistry, 2024, 39(6): 303-311. doi: 10.3866/PKU.DXHX202312006
11. [11]
  Caixia Lin , Zhaojiang Shi , Yi Yu , Jianfeng Yan , Keyin Ye , Yaofeng Yuan . Ideological and Political Design for the Electrochemical Synthesis of Benzoxathiazine Dioxide Experiment. University Chemistry, 2024, 39(2): 61-66. doi: 10.3866/PKU.DXHX202309005
12. [12]
  Yanglin Jiang , Mingqing Chen , Min Liang , Yige Yao , Yan Zhang , Peng Wang , Jianping Zhang . Experimental and Theoretical Investigations of Solvent Polarity Effect on ESIPT Mechanism in 4′-N,N-diethylamino-3-hydroxybenzoflavone. Acta Physico-Chimica Sinica, 2025, 41(2): 100012-. doi: 10.3866/PKU.WHXB202309027
13. [13]
  Yihao Zhao , Jitian Rao , Jie Han . Synthesis and Photochromic Properties of 3,3-Diphenyl-3H-Naphthopyran: Design and Teaching Practice of a Comprehensive Organic Experiment. University Chemistry, 2024, 39(10): 149-155. doi: 10.3866/PKU.DXHX202402050
14. [14]
  Jianfeng Yan , Yating Xiao , Xin Zuo , Caixia Lin , Yaofeng Yuan . Comprehensive Chemistry Experimental Design of Ferrocenylphenyl Derivatives. University Chemistry, 2024, 39(4): 329-337. doi: 10.3866/PKU.DXHX202310005
15. [15]
  Baohua LÜ , Yuzhen LI . Anisotropic photoresponse of two-dimensional layered α-In₂Se₃(2H) ferroelectric materials. Chinese Journal of Inorganic Chemistry, 2024, 40(10): 1911-1918. doi: 10.11862/CJIC.20240105
16. [16]
  Liyang ZHANG , Dongdong YANG , Ning LI , Yuanyu YANG , Qi MA . Crystal structures, luminescent properties and Hirshfeld surface analyses of three cadmium(Ⅱ) complexes based on 2-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)benzoate. Chinese Journal of Inorganic Chemistry, 2024, 40(10): 1943-1952. doi: 10.11862/CJIC.20240079
17. [17]
  Xinhao Yan , Guoliang Hu , Ruixi Chen , Hongyu Liu , Qizhi Yao , Jiao Li , Lingling Li . Polyethylene Glycol-Ammonium Sulfate-Nitroso R Salt System for the Separation of Cobalt (II). University Chemistry, 2024, 39(6): 287-294. doi: 10.3866/PKU.DXHX202310073
18. [18]
  Chi Li , Jichao Wan , Qiyu Long , Hui Lv , Ying Xiong . N-Heterocyclic Carbene (NHC)-Catalyzed Amidation of Aldehydes with Nitroso Compounds. University Chemistry, 2024, 39(5): 388-395. doi: 10.3866/PKU.DXHX202312016
19. [19]
  Runhua Chen , Qiong Wu , Jingchen Luo , Xiaolong Zu , Shan Zhu , Yongfu Sun . 缺陷态二维超薄材料用于光/电催化CO₂还原的基础与展望. Acta Physico-Chimica Sinica, 2025, 41(3): 2308052-. doi: 10.3866/PKU.WHXB202308052
20. [20]
  Min LIU , Huapeng RUAN , Zhongtao FENG , Xue DONG , Haiyan CUI , Xinping WANG . Neutral boron-containing radical dimers. Chinese Journal of Inorganic Chemistry, 2025, 41(1): 123-130. doi: 10.11862/CJIC.20240362