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1.
Solid state Michael addition reaction of indole with α,β-unsaturaled carbonyl compounds was carried out,by which a series of compounds containing three different heterocyclic groups binding to one carbon atom were obtained.In the presence of Lewis acid,indole could undergo the solid state condensation reaction with aromatic ketones and aldehydes or quinones.The solid state reaction showed higher selectivity and yield than solution reaction The structures of products were identified by IR,1H NMR,MS,elemental analysis and X-ray crystal analysis.The reaction mechanism was also proposed.  相似文献   

2.
Strategies for the formation of carbon-carbon bonds from the α-thioaryl carbonyl products of substituted lactams are described. Although direct functionalization is possible, a two step process of oxidation and magnesium-sulfoxide exchange has proven optimal. The oxidation step results in the formation of two diastereomers that exhibit markedly different levels of stability toward elimination, which is rationalized on the basis of quantum mechanical calculations and X-ray crystallography. Treatment of the sulfoxide with i-PrMgCl results in the formation of a magnesium enolate that will undergo an intramolecular Michael addition reaction to form two new stereogenic centers. The relationship between the substitution patterns of the sulfoxide substrate and the efficiency of the magnesium exchange reaction are also described.  相似文献   

3.
A new synthesis of functionalized 1,3-dienes is described based on the palladium catalyzed coupling reaction of 1-(E)-alkenylboronic acids with α-bromo-α,β-unsaturated carbonyl compounds.  相似文献   

4.
Hypervalent iodine(Ⅲ)reagents have been vastly used in many useful organic transformations.In this review article,we highlight the strategies that used the common hypervalent iodine(Ⅲ)reagents as oxidants to synthesize the heterocyclic compounds,based on the patterns of bond formation during the construction of the heterocyclic backbones.  相似文献   

5.
Difluorocarbene generated from the decomposition of fluorosulfonyldifluoroacetic acid (2)reacted with various sodium salts of N-heterocyclic compounds(1) giving the corresponding difluoro-methylated products in acetonitrile at 10—40℃.Benzotriazole(1a),benzimidazole(1b) and imidazole(1c) were converted into 1-(difluoromethyl)benzotriazole(3a),1-(difluoromethyl)benzimidazole(3b) and1-(difluoromethyl)imidazole(3c)respectively.Indole(1d)reacted with 2 to give -(fluorosulfonyldifluoro-acetate)indole(2d) rather than the expected difluoromethylated derivatives.  相似文献   

6.
The solid state reactions of p-nitroacetophenone,acetyl-ferrocene with indole were catalyzed by anhydrous zinc chloride or aluminum chloride,and gave exclusively the 1:2 condensation products.The solid state condensation of aromatic ketones with l-phenyl-3-methyl-5-pyrazolone was also investigated,and the 1:1 and 2:1 condensation products were obtained.The structures of eleven new products were determined by IR,MS,1H NMR and elemental analysis.  相似文献   

7.
Reactions of [NH_4]_2[MS_4](M=Mo,W),CuX(X=Br,I)and PPh_3 in the solid state producedfour mixed-metal sulfur containing clusters{Cu_3MS_3X}(PPh_3)_3S(M=Mo,W;X=Br,I),two of which(1:M=Mo,X=I;2:M=W,X=Br)were structurally determined.Crystals of 1 and 2 are triclinic,space group P(1:a=11.895(3),b=13.107(1),c=20.473(2),α=74.95(6),β=84.87(8),γ=64.27(7)°,Z=2,V=2776.1 ,Rw=0.064 for 6443 observed reflections.2:α=11.876 (1),b=13.065 (2),c=20.325(2),α=74.95(1),β=85.39(1),γ=64.09(1)°,Z=2,V=2737.3,R_w=0.055 for 5303 observedreflections).The results of the structure determination showed that the central units of the two cubane-like cluster compounds are composed of four metal atoms and four non-metal atoms situated at alter-nate comers.The differences of cubane-like cluster compounds obtained from solid state reactions andfrom solution reactions are discussed.  相似文献   

8.
Condensed 1,4-dihydropyridines, which do not contain a substituent in position 4 and which are formed in the reaction of 2-(3-oxoalkyl)-1,3-cycohexanediones with ammonium acetate in acetic acid, undergo disproportionation. Pyridine bases are formed as the result of two competing reactions: disproportionation and oxidation of 1,4-dihydropyridines, intermediates in the heterocyclization of oxo-1,3-diketones with participation of the nitrogen atom, by air oxygen.N. G. Chernyshevskii Saratov State University Saratov 410026. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 647–651, May, 1994. Original article submitted April 22, 1994.  相似文献   

9.
In this review, we systematize data on methods for synthesis of nitrogen-containing heterocyclic compounds cyclocondensation of -haloketones with different compounds.Samara State Technical University, Samara 443010. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–885, July, 1994.  相似文献   

10.
Linalyl alkyl or aryl carbinols were regioselectively synthesized by the reaction ofgeranyl bromide and powdered tin with aldehydes and ketones.  相似文献   

11.
A novel iron-catalyzed oxidative coupling of indoles with α-amino carbonyl compounds has been developed. The transformation provides an attractive approach to the synthesis of 3-acylindoles, with the advantages of easily available starting materials and high functional group tolerance. Furthermore, control experiments imply that a radical process maybe involved in this reaction.  相似文献   

12.
The reactions of -aminopropionic acid N"-acylhydrazides with aromatic and heterocyclic aldehydes and acetone afford compounds that exist in solutions predominantly as mixtures of 2-substituted 3-acylaminotetrahydropyrimidin-4-ones (ATHP) and tautomeric Schiff"s bases. These compounds in the crystalline state probably have structures of ATHP. The ratio of tautomers depends on the type of substituent in the aromatic ring and solvent. The reactions of 2-aryl-3-benzamidotetrahydropyrimidin-4-ones with carboxylic or sulfonic acid chlorides afford derivatives of 1-acyl- and 1-tosyl-3-benzamidotetrahydropyrimidin-4-ones.  相似文献   

13.
The reaction of the lithium enolates of α-aryl carbonyl compounds with cyclopropylmagnesium carbenoids, derived from 1-chlorocyclopropyl p-tolyl sulfoxides with i-PrMgCl at low temperature, resulted in the formation of β-aryl carbonyl compounds bearing a cyclopropane ring at the α-position with one-carbon homologation in variable yields. The reaction was found to be highly stereospecific with respect to the stereochemistry of the cyclopropylmagnesium carbenoids. Mechanism and origin of the stereospecificity of the reaction are also discussed. This is the first example for the insertion of cyclopropanes in between a carbonyl carbon and an α-carbon of carbonyl compounds.  相似文献   

14.
In this review an exhaustive crystallochemical analysis of copper(I) π-complexes with allyl derivatives of heterocyclic compounds has been performed. Structural genesis of inorganic constituents starting from the simplest units to the most complicated aggregates was considered taking into account the specific role of Cu-(C=C) interaction, the construction of the organic ligands, the basicity and nucleophilic activity of their heteroatoms, as well as olefin Cu(I) π-complex preparation route.   相似文献   

15.
Reactions of[NH_4]_2[MS_4](M=Mo,W),AgX(X=Cl,Br,I,CN,SCN)and PPh_3in the solid state produced six new mixed-metal sulfur containing cluster compounds,two ofwhich,{Ag_3MoS_3I}(PPh_3)_3S(1)and{Ag_3WS_3Cl}(PPh_3)_3S·0.5P(S)Ph_3·3H_2O(2),were determinedby single crystal X-ray analysis.The crystal data:1,triclinic,P,a=12.114(2),b=13.420(2),c=20.346(3),α=74.53(1),β=86.73(1),γ=63.74(1)°,Z=2,R=0.043 for 4805 independentdata;2,hexagonal,R3,a=b=16.201(3),c=45.091(10),Z=6,R=0.042 for 2729 independentdata.The central unit{Ag_3MS_3X}(M=Mo,W;X=Cl,I)of the two compounds can be des-cribed as a slightly distorted cube,four corners being formed by the MS_4~(2-) ligand(with a ter-minal S atom).The remaining corners are occupied by one X(Cl or I)atom and three Agatoms(with one PPh_3 ligand bound to each of the latter).The generation of different types ofAg-Mo(W)-S cluster compounds prepared from solid state reactions under different reactiontemperatues is discussed.  相似文献   

16.
A Lewis acid promoted Csp3–H bond functionalization of methyl azaarenes with α-trifluoromethylated carbonyl compounds is described. Catalytic amounts of Yb(OTf)3 provided a straightforward access to the corresponding trifluoromethylated alcohols in excellent yields up to 94% under mild reaction conditions.  相似文献   

17.
Reactions of fluoroaliphatic α,β-unsaturated carbonyl compounds and perfluoro-2,7-dimethylocta-3,5-diene with electrochemically generated peroxydisulfuryldifluoride proceed to give both 1∶1 adducts and fluorosulfatodimerization products, whose formation is explained by generation of heteroallyl and allyl radicals due to the addition of a fluorosulfonyloxy radical to the sterically hindered vinyl carbon atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2207–2209, November, 1999.  相似文献   

18.
19.
《Tetrahedron letters》1986,27(47):5763-5764
Reductive cross-coupling of carbonyl compounds with(α,β-unsaturated esters by SmI2 to ?-lactones was highly accelerated by the addition of hexamethylphosphoric triamide (HMPA).  相似文献   

20.
Yun Liu 《Tetrahedron》2007,63(9):2024-2033
Convenient and regioselective syntheses of 1,2-annulated, and 1,2-, 5,6- and 1,2-, 7,8-bisannulated polycyclic indolizine derivatives have been achieved by one-pot tandem reactions of cyclic N-ylides derived from the corresponding N-substituted pyridinium, quinolinium, and isoquinolinium salts 1-3 with dichloro substituted α,β-unsaturated carbonyl compounds 4-7. The reactions of the N-ylides with 2,3-dichloroindenone 4, 3,4-dichlorocoumarin 5, and 4a,6,7,8a-tetrachloro-1,4-methanonaphthalene-5,8-dione 6 proceed by sequential [3+2] cycloaddition and elimination of hydrogen chlorides from the cycloadducts. On the other hand, reactions of the N-ylides with 2,3-dichloro-1,4-naphthoquinone 7 take place via a novel reaction sequence to give the products 15-17.  相似文献   

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