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1.
NHC‐Catalyzed Asymmetric Synthesis of Functionalized Succinimides from Enals and α‐Ketoamides 下载免费PDF全文
Dr. Lei Wang Qijian Ni Marcus Blümel Tao Shu Prof. Dr. Gerhard Raabe Prof. Dr. Dieter Enders 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8033-8037
The efficient asymmetric synthesis of highly substituted succinimides from α,β‐unsaturated aldehydes and α‐ketoamides via NHC‐catalyzed [3+2] cycloaddition has been developed. The new scalable protocol significantly expands the utility of NHC catalysis for the synthesis of heterocycles and provides easy access to assemble a wide range of succinimides from simple starting materials. 相似文献
2.
The mass spectra of succinimide, four monosubstituted and ten disubstituted saturated succinimides and six unsaturated ( = ethylidene substituted) succinimides are recorded and interpreted. Fragmentation schemes are derived which permit the identification of unknown substituted succinimides obtained by degradation of natural pyrrole pigments. 相似文献
3.
Enantioenriched substituted succinimides are interesting compounds, and their asymmetric organocatalytic synthesis by the conjugated addition of ketones to maleimides has been scarcely explored. This study shows the enantioselective conjugate addition of ketones to maleimides organocatalyzed by a simple primary amine-salicylamide derived from a chiral trans-cyclohexane-1,2-diamine, which provides the desired succinimides in good to excellent yields (up to 98%) and with moderate to excellent enantioselectivities (up to 99%). 相似文献
4.
The NaBH4 reduction of mono- and disubstituted succinimides in the presence of hydrochloric acid leading to ω-carbinol-lactams shows a remarkable regio- and/or stereo-selectivity. The reduction takes place at the most substituted CO in the succinimides. Possible explanations are reviewed. The preparative value of the method is amply illustrated. 相似文献
5.
An unprecedented asymmetric α-sulfenylation of 5H-oxazol-4-ones to N-(sulfanyl)succinimides has been established, to access various α-sulfenylated adducts with good to excellent enantioselectivities (86–95% ee) by utilizing a cinchona alkaloid-derived squaramide as catalyst. The conditions of this α-sulfenylation protocol simultaneously satisfy N-(arylthio)succinimides, N-(benzylthio)succinimides, and N-(alkylthio)succinimides by tuning the substituted groups of 5H-oxazol-4-ones on the 2-position as well as additives. 相似文献
6.
7.
Li L Chen W Yang W Pan Y Liu H Tan CH Jiang Z 《Chemical communications (Cambridge, England)》2012,48(42):5124-5126
A bicyclic guanidine-catalyzed Michael addition of 3-benzyl substituted oxindoles to N-maleimides has been developed to produce oxindole derivatives with a quaternary carbon chiral center at the 3-position in excellent yields and enantio- and diastereoselectivities. This is the first incorporation of N-benzylic α-branched succinimides into 3,3-disubstituted oxindoles. 相似文献
8.
Werner W.K.R. Mederski Manfred BaumgarthMartina Germann Dieter KuxThomas Weitzel 《Tetrahedron letters》2003,44(10):2133-2136
An efficient one-step synthesis of 4-nitro-N-aryl substituted glutarimides, succinimides and maleimides in polyphosphoric acid is described together with the subsequent reduction to the corresponding anilines. The scope and limitation of this cyclocondensation are presented. 相似文献
9.
Cassie A. Goodman Joel B. Eagles Leandre Rudahindwa Christopher G. Hamaker 《合成通讯》2013,43(16):2155-2164
A collection of N-acyl and N-carbamoyl succinimides were prepared by acylation of succinimide with acyl chlorides or by ethylene dichloride (EDC) coupling of carboxylic acids. The x-ray crystal structures of N-benzoyl and N-p-nitrobenzoyl succinimides were determined. The N-acyl succinimides were effective in acylating primary amines, a secondary amine, and an aromatic amine. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
10.
Bibi A. Shah T. Sadiq A. Khalid N. Ullah F. Iqbal A. 《Russian Journal of Organic Chemistry》2019,55(11):1749-1754
Russian Journal of Organic Chemistry - N-Substituted succinimides having different alkyl groups were prepared by the reaction of N-substituted maleimide with aldehydes. A two-component catalyst... 相似文献
11.
Dr. Jose R. Cabrero‐Antonino Dr. Iván Sorribes Dr. Kathrin Junge Prof. Dr. Matthias Beller 《Angewandte Chemie (International ed. in English)》2016,55(1):387-391
Reported herein, for the first time, is the selective ruthenium‐catalyzed reductive alkoxylation and amination of phthalimides/succinimides. Notably, this novel methodology avoids hydrogenation of the aromatic ring and allows methoxylation of substituted imides with good to excellent selectivity for one of the carbonyl groups. The reported method opens the door to the development of new processes for the selective synthesis of various functionalized N‐heterocyclic compounds. As an example, intramolecular reductive couplings to afford tricyclic compounds are presented for the first time. 相似文献
12.
Maximiliano A. Sortino Valdir Cechinel Filho Susana A. Zacchino 《Tetrahedron: Asymmetry》2009,20(10):1106-1108
The CC double bond of non-substituted and substituted maleimides were hydrogenated to the corresponding succinimides by fungal strains. 2- and 2,3-methylated-phenyl-maleimides were enantioselectively reduced to (R)-N-phenyl-3-methylsuccinimide and to trans-(R,R)-N-phenyl-2,3-dimethylsuccinimide respectively by Aspergillus niger, A. flavus and A. fumigatus (conversion 96 to 99%), Fusarium graminearum and Penicillium sp (conversion: 37 and 39%), with 99% ee. 相似文献
13.
Haoru Jin Dr. Chao Zhou Prof. Dr. Hongji Li Prof. Dr. Pinhua Li Prof. Dr. Lei Wang Prof. Dr. Tao Miao 《European journal of organic chemistry》2023,26(38):e202300687
A simple and effective method for the synthesis of 9-sulfenylphenanthrenes was developed via BF3 ⋅ OEt2-mediated annulation of 2-alkynyl biaryls with N-arylthio succinimides at room temperature. Through this methodology, a series of 9-sulfenylphenanthrenes could be efficiently and conveniently obtained in good to excellent yields under mild and metal-free conditions. 相似文献
14.
André U. Augustin Prof. Dr. Peter G. Jones Prof. Dr. Daniel B. Werz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(50):11620-11624
A 1,3-aminothiolation was realized by reacting 2-substituted cyclopropane 1,1-dicarboxylates with sulfonamides and N-(arylthio)succinimides. Under Sn(OTf)2 catalysis the transformation proceeded smoothly to the corresponding ring-opened products bearing the sulfonamide in the 1-position next to the donor and the arylthio residue in the 3-position next to the acceptor. The procedure was extended to the corresponding selenium analogues by employing N-(phenylseleno)succinimides as an electrophilic selenium source. 相似文献
15.
Relationship between enantioselectivity and solute structure on a chiral α1-acid glycoprotein column
Summary The relationship between the enantioselectivity, the retention and the solute structure for N-aminoalkylsuccinimides and 1-alkyl-2′,6′-pipecoloxylidides
have been studied using α1-acid glycoprotein as the chiral stationary phase. Both the enantioselectivity and the retention are highly affected by small
changes of the solute structure in series of homologous compounds. For example, increasing the steric bulk on a basic aliphatic
nitrogen improves the enantioselectivity. It was also demonstrated for the succinimides that the magnitude of the separation
factor was highly affected by the distance between the basic nitrogen and the chiral center. The chiral selectivity was not
lost for the succinimides despite the fact that the basic nitrogen was separated from the chiral center with seven atoms,
which may be an effect of that these compounds contain more than one strong hydrogen bonding group. Substitution in the aromatic
ring of the succinimides also influences both the retention and the chiral selectivity to a large extent. Electronegative
substituents can increase the separation factor but introduction of an alkyl or an alkoxy group in the aromatic ring decreases
the enantioselectivity for the succinimides. 相似文献
16.
A facile,efficient synthesis of 3-(guaiazulen-1-yl)succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions. 相似文献
17.
Alcaide B Almendros P Cabrero G Ruiz MP 《Chemical communications (Cambridge, England)》2007,(45):4788-4790
A single-step catalytic ring expansion approach from 4-oxoazetidine-2-carbaldehydes to enantiopure succinimides has been achieved by the use of a base (DBU) and a thiazolium salt precatalyst. 相似文献
18.
Greta Vastakaite Dr. Claudio E. Grünenfelder Prof. Helma Wennemers 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(18):e202200215
Catalytic stereoselective additions with maleimides are useful one-step reactions to yield chiral succinimides, molecules that are widespread among therapeutically active compounds but challenging to prepare when the maleimide is C-substituted. We present the tripeptide H-Pro-Pro-Asp-NHC12H25 as a catalyst for conjugate addition reactions between aldehydes and C-substituted maleimides to form succinimides with three contiguous stereogenic centers in high yields and stereoselectivities. The peptidic catalyst is so chemoselective that no protecting group is needed at the imide nitrogen of the maleimides. Derivatization of the succinimides was straightforward and provided access to chiral pyrrolidines, lactones, and lactams. Kinetic studies, including a Hammett plot, provided detailed insight into the reaction mechanism. 相似文献
19.
A highly efficient substitution of the vinyl fluoride of perfluoroketene dithioacetals was achieved using trimethylsilylacetate to give 2-perfluoroalkyl succinic acid derivatives and 2-trifluoromethyl succinimides. This chain process was initiated by a catalytic amount of fluoride salt, whereas reaction failed with the corresponding lithium enolate. 相似文献
20.
R. Hekmatshoar M. M. Heravi B. Baghernejad K. Asadolah 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1611-1614
Synthesis of N-alkyl phthalimides and N-alkyl succinimides through alkylation of potassium phthalimide and potassium succinimide in dry media catalyzed by phase-transfer catalyst under microwave irradiation will be reported. The reactions were with fairly high yield. 相似文献