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1.
The reactions of fluoroalkanesulfonyl azides RfSO2N31 with N-alkylindoles 2 have been studied in detail. It was found that both solvent and the amount of the azides seriously affected the product distribution. 1 reacted with equimolar of 2 in ether or 1,4-dioxane affording 2-(N-substituted-indolinylidene)fluoroalkane sulfonylimines 3 as major product; While, treatment of 2 with 2 equiv. of 1 in ethanol, an unexpected product N-substituted-2-fluoroalkanesulfonimino-3-diazo-indolines 4 were obtained in good yield. The reaction mechanism was discussed.  相似文献   

2.
From the carbolithiation of N,N-dimethylamino fulvene (3a) and different ortho-lithiated heterocycles (furan, thiophene and N-methylpyrrole), the corresponding lithium cyclopentadienide intermediate (4a-c) was formed. These three lithiated intermediates underwent a transmetallation reaction with TiCl4 resulting in dimethylamino-functionalised titanocenes 5a-c. When these titanocenes were tested against LLC-PK cells, the IC50 values obtained were of 240, and 28 μM for titanocenes 5a and 5b, respectively. The most cytotoxic titanocene 5c with an IC50 value of 5.5 μM is found to be almost as cytotoxic as cis-platin, which showed an IC50 value of 3.3 μM, when tested on the LLC-PK cell line, and titanocene 5c is approximately 400 times better than titanocene dichloride itself.  相似文献   

3.
The lithiation of 4-heterosubstituted dibenzothiins 1 (phenoxathiin, phenothiazine and thianthrene) with lithium and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 7.5% molar) in THF at temperatures ranging from −90 to −78°C gives the corresponding functionalised organolithium intermediate I, which by reaction with different electrophiles [H2O, D2O, ButCHO, PhCHO, Ph(CH2)2CHO, Me2CO, Et2CO, (CH2)5CO, (CH2)7CO] at the same temperature, followed by hydrolysis, gives the expected functionalised thiols 2. Cyclisation of some thiols 2 under acidic conditions leads to the corresponding seven-membered dibenzo heterocycles 5. In the case of thianthrene 1c, after addition of a carbonyl compound as the first electrophile [MeCHO, ButCHO, Me2CO, Et2CO, (CH2)5CO], the corresponding intermediate II can be lithiated again and react with a second electrophile. Diols 3 are obtained after hydrolysis when a carbonyl compound [ButCHO, PhCHO, Ph(CH2)2CHO, Me2CO, Et2CO, (CH2)5CO] is used as the second electrophile. Acidic cyclisation of diols 3 gives substituted phthalans 6 in almost quantitative yields. Finally, in the case of using carbon dioxide as the second electrophile, phthalides 4 are obtained after acidic hydrolysis.  相似文献   

4.
Cecilia Gómez 《Tetrahedron》2007,63(22):4655-4662
The reaction of phenylcyclopropane (1) with an excess of lithium and a catalytic amount of DTBB (2.5% molar) in THF at room temperature, followed by treatment with an electrophile [Me3SiCl, PhMe2SiCl, t-BuCHO, PhCHO, Me2CO, Et2CO, (CH2)5CO, adamantan-2-one, i-Pr2CO, di(cyclopropyl)ketone] and final hydrolysis with water leads to allylic products 10 or 11 depending on the structure of the electrophile: whereas for chlorosilanes or crowded ketones γ-products 11 are isolated, for aldehydes and non-congested ketones α-products 10 are formed. The application of the same protocol to 1,1-diphenylcyclopropane (7) leads to a mixture of products 13-15 resulting from the introduction of one or two electrophilic fragments to the open-chain mono- or dilithiated intermediate: also in this case the regiochemistry of the reaction is governed by steric reasons.  相似文献   

5.
Tsutomu Fukuda 《Tetrahedron》2005,61(28):6886-6891
Directed lithiation of 1-(triisopropylsilyl)gramines 1 with tert-butyllithium followed by reaction with trimethylsilylmethyl azide produced 4-amino-1-(triisopropylsilyl)gramines 7. The N-tert-butoxycarbonyl derivatives 8 were lithiated selectively at C-5 with tert-butyllithium and the lithiated species were reacted with a variety of electrophiles to give 5-functionalized compounds, 9 and 10. A facile method to produce 3,4,5-trisubstituted indoles from readily available gramine derivatives is thereby established.  相似文献   

6.
From the reaction of Super Hydride (LiBEt3H) with 6-(4-methoxyphenyl) fulvene (1a), 6-(2-fluoro-4-methoxyphenyl) fulvene (1b), and 6-(4-N,N-dimethylaminophenyl) fulvene (1c) lithiated cyclopentadienide intermediates (2a-c) were synthesised. These intermediates were then transmetallated to zirconium with ZrCl4 to give benzyl-substituted zirconocenes bis-[(4-methoxybenzyl)cyclopentadienyl] zirconium(IV) dichloride (3a), bis-[(2-fluoro-4-methoxybenzyl)cyclopentadienyl] zirconium(IV) dichloride (3b) and bis-[(4-N,N-dimethylaminobenzyl)cyclopentadienyl] zirconium(IV) dichloride (3c). All three zirconocenes were characterised by single crystal X-ray diffraction and preliminary in vitro cell tests were performed with the zirconocene derivatives on the LLC-PK cell line in order to determine their cytotoxicity. Zirconocenes 3b and 3c did not show cytotoxicity up to a concentration of 170 μM, while 3a exhibited an IC50 value of 57 μM against LLC-PK.  相似文献   

7.
The reactions of fluoroalkanesulfonyl azides RfSO2N31 with N-alkylindoles 2 have been studied in detail. It was found that both solvent and the amount of the azides seriously affected the product distribution. 1 reacted with an equimolar amount of 2 in ether or 1,4-dioxane affording 2-(N-substituted-indolinylidene)fluoroalkane sulfonylimines 3 as major product; While, the treatment of 2 with two equivalent of 1 in ethanol afforded N-substituted-2-fluoroalkanesulfonimino-3-diazo-indolines 4 as an unexpected product in good yields. The reaction mechanism was discussed.  相似文献   

8.
We wished to prepare planar chiral compounds by the lithiation of acetal 2-ferrocenyl-(4S,5S)-bis(methoxymethyl)-1,3-dioxolane (1) with butyllithium followed by the reaction with an electrophile. However, the desired products were not observed and two unexpected products, 1-ferrocenyl-1-pentanol (4) of the nucleophilic attack product and 2-ferrocenyl-4,5-dimethylene-1,3-dioxolane (5) of the proton abstraction product, were isolated. Because the nucleophilic attack on acetal carbon is rarely reported so far and both products 4 and 5 may have some potential uses in organic synthesis, these unexpected reactions are investigated in detail. The mechanisms of these reactions are discussed.  相似文献   

9.
A novel synthesis of enantiopure hydroxyethylamine isosteres 1 has been developed. Reaction of lithiated β-sulfinylethylamines 3 with N-Cbz-imines generated in situ from α-amino-sulfones 4 afforded in good to excellent yields and moderate stereocontrol the 2-sulfinyl-1,3-diamines 2. The latter were submitted to the nonoxidative Pummerer reaction (NOPR) in CH2Cl2, that produced the target compounds 1 in very good yields with inversion of configuration. In some cases, the use of acetonitrile as solvent resulted in a double-inversion pathway, leading for example to the oxazolidinone 5. The total synthesis of an epimer of Saquinavir has been achieved by this method.  相似文献   

10.
The synthesis and the characterization of some new aluminum complexes with bidentate 2-pyrazol-1-yl-ethenolate ligands are described. 2-(3,5-Disubstituted pyrazol-1-yl)-1-phenylethanones, 1-PhC(O)CH2-3,5-R2C3HN2 (1a, R = Me; 1b, R = But), were prepared by solventless reaction of 3,5-dimethyl pyrazole or 3,5-di-tert-butyl pyrazole with PhC(O)CH2Br. Reaction of 1a or 1b with (R1 = Me, Et) yielded N,O-chelate alkylaluminum complexes (2a, R = R1 = Me; 2b, R = But, R1 = Me; 2c, R = Me, R1 = Et). Compound 1a was readily lithiated with LiBun in thf or toluene to give lithiated species 3. Treatment of 3 with 0.5 equiv of MeAlCl2 or AlCl3 yielded five-coordinated aluminum complexes [XAl(OC(Ph)CH{(3,5-Me2C3HN2)-1})2] (4, X = Me; 5, X = Cl). Reaction of 5 with an equiv of LiHBEt3 generated [Al(OC(Ph)CH{(3,5-Me2C3HN2)-1})3] (6). Complex 6 was also obtained by reaction of 3 with 1/3 equiv of AlCl3. Treatment of 5 with 2 equiv of AlMe3 yielded complex 2a, whereas with an equiv of AlMe3 afforded a mixture of 2a and [Me(Cl)AlOC(Ph)CH{(3,5-Me2C3HN2)-1}] (7). Compounds 1a, 1b, 2a-2c and 4-6 were characterized by elemental analyses, NMR and IR (for 1a and 1b) spectroscopy. The structures of complexes 2a and 5 were determined by single crystal X-ray diffraction techniques. Both 2a and 5 are monomeric in the solid state. The coordination geometries of the aluminum atoms are a distorted tetrahedron for 2a or a distorted trigonal bipyramid for 5.  相似文献   

11.
N,N-dicyclohexyl-N-ferrocenoylurea 2, N,N-diisopropyl-N-ferrocenoylurea 3, N,N-di-p-tolyl-N-ferrocenoylurea 4 and N,N-di-tert-butyl-N-ferrocenoylurea 5 were obtained by reaction of ferrocenecarboxylic acid 1 with N,N-dicyclohexylcarbodiimide (DCC), N,N-diisopropylcarbodiimide (DIC), N,N-di-p-tolylcarbodiimide 10 and N,N-di-tert-butylcarbodiimide 11, respectively. Both N-tert-butyl-N-ethyl-N-ferrocenoylurea 6 and N-tert-butyl-N-ethyl-N-ferrocenoylurea 7 were obtained by reaction of 1 with N-tert-butyl-N-ethylcarbodiimide 12. In all cases a small amount of ferrocenecarboxylic anhydride 8 was formed as a by-product. All compounds were characterized by 1H NMR, 13C NMR, IR and MS. Single crystal X-ray structural analyses were made of 2, 3 and 4. From the consistent results, the reaction products of 1 with carbodiimides appear different from those proposed by some earlier workers. With N-(3-dimethylaminopropyl)-N-ethylcarbodiimidehydrochloride 9 ferrocenoylurea was not isolated, but the main product was rather 8. The suitability of 8 as acylation reagent was applied by using 9 to obtain N-(3-triethoxysilyl)-propylferrocenecarboxamide in a one-pot reaction from 1 and 3-(triethoxysilyl)-propylamine.  相似文献   

12.
Abdeslam Abou 《Tetrahedron》2007,63(28):6625-6634
The lithiation of 1-choro- and 1-bromo-6-chlorohex-1-yne (2, 3) with lithium naphthalene in the presence of benzaldehyde in THF at −78 °C leads after hydrolysis with water to the corresponding chloroalkynol (5) resulting from a regioselective lithiation at the alkynylic position. However, the lithiation of 1-chloro-6-iodohex-1-yne (4) under the same reaction conditions and using pentan-3-one as electrophile leads to the corresponding chloroalcohol (6) from the exclusive lithiation at the aliphatic carbon-iodine bond. Double lithiation of compounds 2 and 3 under Barbier conditions allows the isolation of diols (9), whereas the two-step process leads to differently substituted diols 13. The monolithiation of (E)-1-bromo-6-chlorohex-1-ene (14) under the above conditions and using pentan-3-one as electrophile affords a mixture of chloroalcohols 15 and 16, the process being not stereospecific. However, the lithiation of the same starting material with t-BuLi leads exclusively to a bromine-lithium exchange with retention of the configuration, so after treatment with pentan-3-one only compound 16 was isolated. Finally, whereas double lithiation of compound 14 under the conditions for compounds 9 gives the mixture of compounds 18 and 19, the tandem process involving the t-BuLi-promoted bromine-lithium exchange as the first step followed by lithiation under DTBB-catalysed conditions allows the isolation of (E)-diols 19 as the only reaction products isolated.  相似文献   

13.
The PtCl2-catalyzed cyclization reaction of ortho-alkynylphenyl acetals 1 in the presence of COD (1,5-cyclooctadiene) produces 3-(α-alkoxyalkyl)benzofurans 2 in good to high yields. For example, the reaction of acetaldehyde ethyl 2-(1-octynyl)phenyl acetal (1a), acetaldehyde ethyl 2-(cyclohexylethynyl)phenyl acetal (1c), and acetaldehyde ethyl 2-(phenylethynyl)phenyl acetal (1f) in the presence of 2 mol % of platinum(II) chloride and 8 mol % of 1,5-cycloocatadiene in toluene at 30 °C gave the corresponding 2,3-disubstituted benzofurans 2a, 2c, and 2f in 91, 94, and 88% yields, respectively. Moreover, the reaction of N-methoxymethyl-2-alkynylanilines 3 was catalyzed by PdBr2, affording the corresponding 2,3-disubstituted indoles 4 in moderate yields. For example, the reaction of N-methoxymethyl-2-(1-pentynyl)-N-tosylaniline (3a) and N-methoxymethyl-2-(phenylethynyl)-N-tosylaniline (3b) in the presence of 10 mol % of PdBr2 in toluene at 80 °C gave 3-methoxymethyl-2-propyl-1-tosylindole (4a) and 3-methoxymethyl-2-phenyl-1-tosylindole (4b) in 33 and 33% yields, respectively.  相似文献   

14.
The reactions of cyclotriphosphazene, N3P3Cl6 (1), in a 1:1.2 stoichiometry with the sodium derivative of seven diols [ethane- (2a), 1,3-propane- (2b), 1,4-butane- (2c), 1,5-pentane- (2d), 1,6-hexane- (2e), 1,8-octane- (2f) and 1,10-decane- (2g) diol] in THF solution at room temperature have been used to investigate the effect of chain length on the formation of reaction products. Although no new products were found for the reaction of 1 with diols 2a-c compared to those in the literature using other bases and solution conditions, the reactions of 1 with the diols 2d-g gave six different types of products, whose structures have been characterized by elemental analysis, mass spectrometry, 1H and 31P NMR spectroscopy; ansa compounds N3P3Cl4[O(CH2)nO], (5d-5g); single-bridged compounds N3P3Cl5[O(CH2)nO]N3P3Cl5(6d-6f); double-bridged compounds N3P3Cl4[O(CH2)nO]2N3P3Cl4 (7d-7g, syn and anti) and triple-bridged compounds, N3P3Cl3[O(CH2)nO]3N3P3Cl3 (8d-f). Where suitable single crystals were obtained, X-ray crystallographic studies confirmed the structures of two ansa compounds (5d and 5f), one single-bridged compound (6e), and five double-bridged compounds (meso-anti for 7d, 7e, 7f and meso-syn for 7d and 7f). 31P NMR measurements of the reaction mixtures were used to quantify the formation of products for the reactions 1 with all the diols, 2a-g; it is found that, with increasing chain length of the diol, there is a decrease in the products formed by intramolecular reactions (spiro and ansa derivatives) and a concomitant increase in the amounts of products formed by intermolecular reactions (single-, double- and triple-bridged derivatives) of cyclophosphazene.  相似文献   

15.
The β-(trifluoromethyl)vinyl sulfides on treatment with n-BuLi/TMEDA at −78 °C were readily lithiated at an α-position of the sulfanyl group, and the generated β-trifluoromethyl-α-sulfanylvinyl anions were reacted with a variety of electrophiles to give the corresponding β-trifluoromethyl-α-functionalized-vinyl sulfides 4aa-4aq in good to excellent yields. The reactivity of some products has been examined. The palladium-catalyzed cross-coupling reaction as well as homo-coupling reaction of 4af provided the corresponding products in good yields, respectively. The Diels-Alder reaction of cyclic dienes and 14 derived from 4ao provided the desired six-membered cyclic products with high endo-trifluoromethyl group selectivity.  相似文献   

16.
Chemical fractionation of the southern Australian marine sponge Phoriospongia sp. (CMB-03107) yielded phorioadenine A (1) as a nematocidal agent and the first reported example of a 6-N-acyladenine natural product. The structure of 1 was confirmed by spectroscopic analysis and the chemical synthesis of racemic (1a) and enantiomeric (1b) analogues. HPLC–ESIMS analysis of the crude sponge extract with comparisons to the synthetic 6-N-acyladenosine 2a provided evidence that the biosynthetically related adenosine, phorioadenosine A (2), was present as a trace co-metabolite. The rare starfish metabolite asterubine (3) was also isolated as a co-metabolite, and its structure confirmed by spectroscopic analysis and chemical synthesis. Biological investigations confirmed that natural products 13 and synthetic analogues 1ae and 2a were not cytotoxic to multiple mammalian cancer cell lines, or Gram-positive or -negative bacteria. Nematocidal activity (inhibition of larval development of Haemonchus contortus) detected in the Phoriospongia sp. extract was attributed to 1 (LD99 31 μg/mL), with preliminary structure–activity relationship investigations confirming the importance of the N-acyl side chain.  相似文献   

17.
Yong-Hua Yang 《Tetrahedron》2006,62(10):2420-2427
Benzoxazoles 2 can be smoothly synthesized by treatment of starting materials of N-(2-hydroxyaryl) cyclopropyl amides 1 with PPh3/CCl4 in acetonitrile in good yields. When PPh3/CBr4/MS 4 Å was used in the reaction system, the corresponding ring-expanding products 3 were obtained in moderate to good yields in acetonitrile at 80 °C. Using DCE as a solvent in this reaction, the corresponding 2-(3-chloropropyl)benzoxazoles 5 were obtained as major products.  相似文献   

18.
The reaction of N-(5-methyl-2-thienylmethylidene)-2-thiolethylamine (1) with Fe2(CO)9 in refluxing acetonitrile yielded di-(μ3-thia)nonacarbonyltriiron (2), μ-[N-(5-methyl-2-thienylmethyl)-η11(N);η11(S)-2-thiolatoethylamido]hexacarbonyldiiron (3), and N-(5-methyl-2-thienylmethylidene)amine (4). If the reaction was carried out at 45 °C, di-μ-[N-(5-methyl-2-thienylmethylidene)-η1(N);η1(S)-2-thiolethylamino]-μ-carbonyl-tetracarbonyldiiron (5) and trace amount of 4 were obtained. Stirring 5 in refluxing acetonitrile led to the thermal decomposition of 5, and ligand 1 was recovered quantitatively. However, in the presence of excess amount of Fe2(CO)9 in refluxing acetonitrile, complex 5 was converted into 2-4. On the other hand, the reaction of N-(6-methyl-2-pyridylmethylidene)-2-thiolethylamine (6) with Fe2(CO)9 in refluxing acetonitrile produced 2, μ-[N-(6-methyl-2-pyridylmethyl)-η1 (Npy);η11(N); η11(S)-2-thiolatoethylamido]pentacarbonyldiiron (7), and μ-[N-(6-methyl-2-pyridylmethylidene)-η2(C,N);η11(S)-2- thiolethylamino]hexacarbonyldiiron (8). Reactions of both complex 7 and 8 with NOBF4 gave μ-[(6-methyl-2-pyridylmethyl)-η1(Npy);η11(N);η11(S)-2-thiolatoethylamido](acetonitrile)tricarbonylnitrosyldiiron (9). These reaction products were well characterized spectrally. The molecular structures of complexes 3, 7-9 have been determined by means of X-ray diffraction. Intramolecular 1,5-hydrogen shift from the thiol to the methine carbon was observed in complexes 3, 7, and 9.  相似文献   

19.
Novel condensation reaction of tropone with N-substituted and N,N′-disubstitued barbituric acids in Ac2O afforded 5-(cyclohepta-2′,4′,6′-trienylidene)pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (8a-f) in moderate to good yields. The 13C NMR spectral study of 8a-f revealed that the contribution of zwitterionic resonance structures is less important as compared with that of 8,8-dicyanoheptafulvene. The rotational barriers (ΔG) around the exocyclic double bond of mono-substituted derivatives 8a-c were obtained to be 14.51-15.03 kcal mol−1 by the variable temperature 1H NMR measurements. The electrochemical properties of 8a-f were also studied by CV measurement. Upon treatment with DDQ, 8a-c underwent oxidative cyclization to give two products, 7 and 9-substituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborates (11a-c·BF4 and 12a-c·BF4) in various ratios, while that of disubstituted derivatives 8d-f afforded 7,9-disubstituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborate (11d-f·BF4) in good yields. Similarly, preparation of known 5-(1′-oxocycloheptatrien-2′-yl)-pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (14a-d) and novel derivatives 14e,f was carried out. Treatment of 14a-c with aq. HBF4/Ac2O afforded two kinds of novel products 11a-c·BF4 and 12a,c·BF4 in various ratios, respectively, while that of 14d-f afforded 11d-f. The product ratios of 11a-c·BF4 and 12a-c·BF4 observed in two kinds of cyclization reactions were rationalized on the basis of MO calculations of model compounds 20a and 21a. The spectroscopic and electrochemical properties of 11a-f·BF4 and 12a-c·BF4 were studied, and structural characterization of 11c·BF4 based on the X-ray crystal analysis and MO calculation was also performed.  相似文献   

20.
Pyrolysis of carboxylic acid group at C-4 of 2, an oxidation product from the C19-diterpenoid alkaloid lycoctonine 1, generated an unexpected but novel rearranged product 13 (37%). The structure of 13 was confirmed by its 2D NMR data and its single crystal X-ray crystallographic analysis. In addition, hydrogenolysis of 13 in the presence of acetic acid yielded the N-C6 bond fission products 16 and 17, which represents the first hydrogenolysis involving the breakage of the N-C6 bond of the diterpenoid alkaloids. Some new observations on the oxidation of lycoctonine 1 were described as well.  相似文献   

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