一锅法合成新型7-苯基-1,4,5,6,7,8-六氢喹啉酮衍生物

以5-苯基-1,3-环己二酮,醛,乙酰乙酸乙酯(或乙酰丙酮)和乙酸铵为原料,在无水乙醇中经一锅反应合成了14个新型的7-苯基-1,4,5,6,7,8-六氢喹啉酮衍生物,总收率85%~95%,其结构经¹H NMR, ¹³C NMR, IR和HR-MS表征。采用X-ray单晶衍射研究了2-甲基-4,7-二苯基-5-氧代-1,4,5,6,7,8-六氢喹啉顺反异构体(5a和5a′)的晶体结构。结果表明：5a空间群为C2/c, a=9.458 35(19) ,b=19.789 0(4) ,c=11.040 9(2) , α=90°, β=105.614(2)°, γ=90°,V=1 990.28(7) ³, Z=4, μ=0.673 mm^-1, F(000)=824; 5a′空间群为C2/c, a=9.770 2(5) , b=19.981 0(10) , c=10.430 1(4) , α=90°, β=98.361(5)°, γ=90°, V=2 014.51(17) ³, Z=4, μ=0.665 mm^-1, F(000)=824。     

三烯胺催化2,5-二烯酮的远端不对称Mannich反应

利用三烯胺机制活化环状2,5-二烯酮,对远端的不对称Mannich反应进行研究。用手性伯胺催化环状2,5-二烯酮原位生成三烯胺中间体,与苯甲醛和苯胺经三组分一锅法反应获得了7个新型的远端不对称Mannich加成产物,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)表征。在最佳反应条件下,收率达87%,对映选择性达78%。     

树脂糖苷Albinoside III的新型喹诺糖模块的合成

树脂糖苷Albinoside III是一种良好的多药耐药外排泵抑制剂,本文探索了高效构建树脂糖苷中喹诺糖模块的方法。从D-葡萄糖硫苷出发,采用一锅法,经4步反应构建了D-喹诺糖模块A,总收率58.4%;从4,6-位苄叉保护的D-葡萄糖硫苷出发,通过3-位选择性的PMB保护,经5步反应构建了正交保护的D-喹诺糖模块E,总收率28.5%。该合成路线中涉及8个新化合物,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)表征。     

微波促进下4-乙炔基苯磺酰胺的“一锅法”合成

以3-(4-氯磺酰苯基)-2,3-二溴丙酸和氨水（2.2 eq）为原料,以 DMF为溶剂,经微波辐射25 s,磺酰胺化和脱溴脱羧反应可同步进行,立体选择性地合成中间体(Z)-4-(2-溴乙烯基)苯磺酰胺;该中间体不需分离,直接向反应体系中加入1,8-二氮杂环[5,4,0]十一烯-7 (DBU,2eq),再微波辐射1 min,“一锅法”得到4-乙炔基苯磺酰胺,并通过1H NMR和13C NMR和IR进行了表征,收率达70%。     

聚苯乙烯负载氯化铁催化一锅法合成β-氨基酮类衍生物

制备了聚苯乙烯负载型氯化铁催化剂(PS-FeCl3),并通过红外光谱、X射线衍射、扫描电子显微镜等技术手段进行了表征。 在PS-FeCl3催化下,以苯乙酮、芳醛和芳胺为原料,采用一锅法Mannich反应合成了一系列β-氨基酮衍生物。 制备的催化剂性能稳定,使用4次仍保持较高活性。     

A Novel Approach to the Synthesis of 1,3,4-Thiadiazole-2-amine Derivatives

The main purpose of the study was the development of a new method for synthesis of 1,3,4-thiadiazol-2-amine derivatives in a one-pot manner using the reaction between a thiosemicarbazide and carboxylic acid without toxic additives such as POCl₃ or SOCl₂. The reaction was investigated in the presence of polyphosphate ester (PPE). It was found that, in the presence of PPE, the reaction between the thiosemicarbazide and carboxylic acid proceeds in one-pot through three steps with the formation of corresponding 2-amino-1,3,4-thiadiazole. Using the developed approach five, 2-amino-1,3,4-thiadiazoles were synthesized. The structures of all compounds were proven by mass spectrometry, IR, and NMR spectroscopies.     

CS-MCM-48复合载体固定化脂肪酶催化苯乙酮一锅法还原转酯化拆分反应

将天然聚合物壳聚糖(CS)涂覆在介孔分子筛MCM-48表面制得CS-MCM-48复合载体,控制CS与介孔分子筛MCM-48质量比为1∶10时,CS-MCM-48的比表面积、平均孔径和孔容分别为408m2/g、2.14nm和0.38cm3/g。在磷酸盐缓冲溶液-异辛烷混合溶剂中制备了固定化假单胞菌脂肪酶(Pseudomonas Cepacia Lipase,PSL)PSL/CS-MCM-48,并用于潜手性苯乙酮一锅法还原转酯化手性拆分反应。结果表明,PSL/CS-MCM-48的催化活性和对映选择性均明显优于纯介孔分子筛MCM-48和壳聚糖制备的固定化酶PSL/MCM-48和PSL/CS。甲苯作溶剂,反应温度为40℃时,底物1-苯乙醇转化率达15.3%,产物(R)-乙酸苯乙酯和(S)-1-苯乙醇的对映体过量值分别为99%和18.0%,对映选择性参数E值达237,固定化酶PSL/CS-MCM-48显示出良好的手性拆分性能。     

双消除法一锅合成甲硫芳炔化合物

描述了一种方便的合成甲硫芳炔化合物的新方法. 利用亲核硫试剂甲硫甲基苯基砜(methylthiomethyl phenyl sulfone, MP-S)与芳香醛的“一锅反应”, 成功地合成了一系列甲硫芳炔化合物1a～1h．通过对各阶段形成的中间体的分析, 探讨了1的形成机制．实验结果表明, 一锅反应经历了双离去基中间体2的形成和后续的两次消除过程．该方法原料易得, 操作简单, 可得到较好的产率(＞70%). 此外, 反应还具有副产物少、容易分离和纯化的优点．     

Front Cover: One-Pot Catalytic Synthesis of Optically Active Drug (S)-Clopidogrel (Eur. J. Org. Chem. 40/2023)

A first catalytic preparation of the popular antiplatelet drug (S)-clopidogrel, known with the tradename of Plavix, has been developed in a one-pot and innovative approach. The synthesis can be performed using commercially available ortho-chlorobenzaldehyde, 1-naphthylsulfonyl acetonitrile, tert-butyl hydroperoxide (TBHP), 4,5,6,7-tetrahydrothieno[3,2-c]pyridine and 20 mol % of a quinidine derived organocatalyst in a single solvent. A Knoevenagel/asymmetric epoxidation/domino ring-opening esterification (DROE) sequence enabled to obtain (S)-clopidogrel in 61 % overall yield and 62 % ee. Fine optimization of the reaction conditions proved to be crucial to set up a selective and efficient process.     

Three Component Synthesis of 4-Aryl-2-aminothiazoles under Transition-Metal Free Conditions

An efficient three-component synthesis of 4-aryl-2-aminothiazoles was reported. Phenyl-thioureas reacted with 2-bromoacetophenones to form 4-aryl-2-aminothiazoles through cyclization, and the subsequent C−N bonding with benzyl/allyl bromides gave the desired disubstituted thiazoles smoothly. The protocol features transition-metal free, short reaction time, easily available starting materials, good yields and broad substrate scope, showing potential synthetic value for the synthesis of a variety of biologically or pharmaceutically active compounds.