Synthesis of α-sulfanyl-β-amino acid derivatives by using nanocrystalline magnesium oxide
作者:M. Lakshmi Kantam、Koosam Mahendar、Bojja Sreedhar、Boyapati. M. Choudary、Suresh K. Bhargava、Steven H. Priver
DOI:10.1016/j.tet.2010.05.002
日期:2010.7
The Mannich-type reaction between alkyl, aryl and heterocyclic aldimines and sulfonium salts for the synthesis of α-sulfanyl-β-amino acidderivatives by using nanocrystalline magnesium oxide (NAP-MgO) is described. These products are obtained in moderate to high yields with moderate diastereoselectivities. The configuration of ethyl-3-[(4-methylphenyl)sulfonyl]amino}-2-(methylsulfanyl)-3-(4-nitrophenyl)propanoate
描述了烷基,芳基和杂环亚胺与M盐之间的曼尼希型反应,用于通过使用纳米晶状氧化镁(NAP-MgO)合成α-硫烷基-β-氨基酸衍生物。这些产品以中等至高收率获得,具有适度的非对映选择性。X射线衍射技术已证实3-[[(4-甲基苯基)磺酰基]氨基} -2-(甲基硫烷基)-3-(4-硝基苯基)丙酸乙酯(主要异构体)的构型是抗,并与基于1 H NMR光谱的赋值一致。这些α-硫烷基-β-氨基酸衍生物是具有强生物活性的药物的重要组成部分。
A GREEN SOLVENTLESS PROTOCOL FOR THE SYNTHESIS OF<i>N</i>-SULFONYLIMINES IN THE PRESENCE OF SILICA SULFURIC ACID AS AN EFFICIENT, HETEROGENEOUS AND REUSABLE CATALYST
and isomerization or rearrangement of N-sulfonylaziridines.2' However, there are some obvious drawbacks in these methods, such as long reaction times, unsatisfactory yields, formation of toxic by-products, the use of expensive and hazardous reagents as well as solvents, and tedious purification. Furthermore, some methods involve cumbersome and multi-step procedures. Therefore, it seems highly desirable
3-Methyl-1-Sulfonic acid imidazolium chloride as a new, efficient and recyclable catalyst and solvent for the preparation of N-sulfonyl imines at room temperature
作者:M. A. Zolfigol、A. Khazaei、A. R. Moosavi-Zare、A. Zare
DOI:10.1007/bf03246053
日期:2010.9
New Brønsted acidic ionic liquid, 3-methyl-1-sulfonic acid imidazolium chloride [Msim]Cl} was used as an efficient, green and reusable catalyst and solvent for the synthesis of N-sulfonyl imines via the condensation of sulfonamides with aldehydes as well as isatin. The reactions proceeded at room temperature and the title compounds were obtained in high to excellent yields and in relatively short
γ-Carbon Activation through N-Heterocyclic Carbene/Brønsted Acids Cooperative Catalysis: A Highly Enantioselective Route to δ-Lactams
作者:Yonglong Xiao、Jinxin Wang、Wenjing Xia、Shuangjie Shu、Shenchao Jiao、Yu Zhou、Hong Liu
DOI:10.1021/acs.orglett.5b01827
日期:2015.8.7
A γ-carbon activation method that operates through N-heterocyclic carbene/Brønsted acidcooperativecatalysis for highly enantioselective synthesis of δ-lactams is reported. The protocol allows the challenging remote γ-carbon control of regioselectivity and enantioselectivity through introduction of an appropriate γ-leaving group in the enals. The reaction offers good yields and excellent enantioselectivities
Silica-supported Zinc Chloride (ZnCl2/SiO2)-induced Efficient Protocol for the Synthesis of N-sulfonyl imines and 2-Arylbenzothiazole
作者:Hanan A. Soliman、Mahmoud El-Shahat、Abdel-Ghany Soliman
DOI:10.2174/1570178615666181025120307
日期:2019.5.30
straightforward strategy for the synthesis of N-sulfonyl imine derivatives from sulfonamides and aryl aldehydes utilizing Silica-supported zinc chloride (ZnCl2/SiO2, silzic) as a catalyst under solvent-free conditions has been developed. 2-Arylbenzothiazole derivatives were also synthesized by the reaction of 2-aminothiophenol with aryl aldehydes under the same conditions. This procedure has advantages