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1.
2-Methyl-2-propenyl- (I) and 2-Butenylmagnesium halide (II) react with bicyclo[2.2.1]hept-2-en (III) erhaltenen -Addukte (IV) und (V) lagern sich converted by heating under opening of one 5-ring. On the basis of the products of hydrolysis, the dialkenylcyclopentanes (X) and (XI), formed by conversion of (V), the mechanism of this reaction hitherto unknown for a saturated 5-cyclic compound is discussed. 相似文献
2.
E.G. Frandsen 《Tetrahedron》1977,33(8):869-873
The reaction of 4- and 5-aryl-3-methylthio-1,2-dithiolylium iodides with 4-hydroxy-6-methyl-2-pyran-2-one and 4-hydroxycoumarin has been studied. 4-Substituted salts yielded 3-aryl-7-methyl-2-thioxo-2,5-pyrano [3,2-c]pyran-5-ones and 3-aryl-2-thioxo-2H,5H-pyrano[3,2-c]benzo[e]pyran-5-ones, respectively, whereas 5-substituted salts gave rise to 3-(5′-aryl-1′,2′-dithiol-3′-ylidene)-6-methyl-2-pyran-2,4-diones and 3-(5′-aryl-1′,2′-dithiol-3′-ylidene)-2-benzo [b]-pyran-2,4-diones. 相似文献
3.
Claudine Augé Serge David Cécile Mathieu Christine Gautheron 《Tetrahedron letters》1984,25(14):1467-1470
Glycosidation of disaccharides I and III with a system of five immobilized enzymes gave excellent yields of trisaccharides -Gal-(1→4)--GlcNAc-(1→6)--Gal ¦ the I(Ma) determinant ¦ and -Gal-(1→4)--Glc-NAc-(1→3)--Gal, on the milimole scale. 相似文献
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Max Herberhold Cornelius G. Kreiter Gűnter O. Wiedersatz 《Journal of organometallic chemistry》1976,120(1):103-130
The temperature-dependent 1H NMR spectra of acetylacetonatebis(ethylene)-rhodium, (acac)Rh(C2H4)2 (I), of some related complexes containing methoxy-substituted ethylenes have been measured in toluene-d8 solution. Both monosubstituted [(acac)Rh(C2H4)(olefin), olefin = tetramethoxyethylene (II), - and -dimethoxyethylene (III and IV)] and disubstituted [(acac)Rh(olefin)2, olefin = - and -dimethoxyethylene (V and VI), methyl vinyl ether (VII)] derivatives of I have been investigated with respect to hindered intramolecular movements of the ligands. The barriers of olefin rotation increase with an increasing number of methoxy substituents. When the olefin rotation is frozen out; the methoxy substituents of the olefins tend to be turned away from the acetylacetonate ligand unless steric interaction occurs between the two π-coordinated olefins. A hindered movement of the acetylacetonate ligand has been observed in II and V. For this movement which is independent of the olefin rotation, a degenerate rearrangement is proposed of the tetragonal-planar complexes via a tetrahedral transition state. 相似文献
6.
C.C. Lee K.J. Demchuk W.J. Pannekoek R.G. Sutherland 《Journal of organometallic chemistry》1978,162(2):253-269
Ligand exchange reactions between phenanthrene or 9,10-dimethylphenanthrene with ferrocene effected in the presence of AlCl3-Al were carried out under a variety of conditions. With phenanthrene (I), hydrogenation at the C-9 and C-10 positions could take place during the reaction and the cationic products obtained were the η6-phenanthrene-η5-cyclopentadienyliron and η6-9,10-dihydro-phenanthrene-η5-cyclopentadienyliron moncations (II and III), and the η6-phenanthrene---η5-cyclopentadienyliron and η6-9,10-dihydrophenanthrene---η5-cyclopentadienyliron dications (IV and V). With 9,10-dimethylphenanthrene (VI), reactions carried out in refluxing cyclohexane gave the non-hydrogenated η6-9,10-dimethylphenanthrene-η5-cyclopentadienyliron monocation (VII) and η6-9,10-dimethylphenanthrene---η5-cyclopentadienyliron dication (VIII). When higher temperatures were used in an attempt to promote hydrogenation, decomposition predominated and no cationic product could be obtained. These finding are discussed and contrasted with previous results obtained from similar reactions using anthracene or 9,10-dimethylanthracene. 相似文献
7.
Ronald E. Banks Ismail M. Farhat Roy Fields Robin G. Pritchard Mohamad M. Saleh 《Journal of fluorine chemistry》1985,28(3):325-340
The nitrosoarenes ArNO (Ar = C6H5, 2-MeC6H4, 2,4,6- Me3C6H2 and C6F5) have been condensed with 4-(dichloroamino)- tetrafluoropyridine to provide the azoxy-compounds pyFN()Ar (pyF = 2,3,5,6-tetrafluoro-4-pyridyl); de-oxygenation of the first three with triphenylphosphine or triethyl phosphite gave the corresponding azo-compounds, and the reverse reaction was achieved in the case of pyFNNC6H2Me3-2,4,6 using peroxytrifluoroacetic acid. Thermolysis of 4-azidotetrafluoropyridine in the presence of pentafluoronitrosobenzene provided the perfluorinated azoxy-compound pyFN()C6F5. X-Ray methods have been used to determine the molecular geometry of pyFN()C6H2Me3-2,4,6. 相似文献
8.
Thomas W. Bell 《Tetrahedron letters》1980,21(36):3443-3446
Hydroboration-oxidation of the bi-1-cyclohexen-1-yls 1 and 8b gave single 1,4-diols, 2 and 10b, respectively, whereas the chiral bi-1-cyclohexen-1-yl 8a, synthesized from (?)--3,5-dimethylcyclohexanone, led to a mixture of two 1,4-diols (9a and 10a). 相似文献
9.
Dale F. Shellhamer Mark L. Ragains Bruce T. Gipe Victor L. Heasley Gene E. Heasley 《Journal of fluorine chemistry》1982,20(1):13-18
We would like to report data which support a free radical pathway for reaction of xenon difluoride (XeF2) with alkenes in organic solvent. Radical intermediates have been proposed for reaction of XeF2 to double bonds. For example, a radical pathway was suggested for the gas phase reaction of XeF2 to ethylene and propene [1]. Zupan speculated on a radical cation pathway for the acid catalyzed reaction of XeF2 with alkenes but gave no experimental evidence for this mechanism [2,3]. Radical cation intermediates were demonstrated for the reaction of XeF2 to aromatics by Filler [4]. Acid catalyzed ionic reactions to unsaturated hydrocarbons have been reviewed [5].Zupan and Pollak have shown that alkenes do not react in aprotic solvent with XeF2 at low concentrations of alkene unless acid catalyst is present [3]. However, we observed that illumination of a dilute solution of or -1-phenylpropenes (I) or (II) in methylene chloride at 0° with a 270 watt sunlamp produced IIIa and IIIb in less then two hours (Table). Furthermore, at high concentration of (I) and (II), a spontaneous reaction occurred in the dark between XeF2 and these styrenes. The reaction conditions for both of these reactions imply a radical mechanism — the latter a molecule-induced pathway. 相似文献
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The conversion of 2-acylamino-3-amino-1,4-naphthoquinones (II) to the corresponding 2-substituted 1H-naphth[2,3-d]imidazole-4,9-diones (I) under both alkaline and acid catalyzed conditions has been effected and the results compared. Treatment of 3-(4′-chlorobutanonyl-amino)-3-amino-1,4-naphthoquinone (He) with aqueous ethanolic sodium hydroxide solution gives 1,2-butanonaphth[2,3-d]imidazole-4,9-dione (V); whereas, treatment of lie with refluxing formic acid gave 2-(4′-chlorobutyl)-1H-naphth[2,3-d]imidazole-4,9-dione. Treatment of 2-substi-tuted 1H-naphth[2,3-d]imidazole-4,5-diones in DMF with alkyl halides in the presence of potassium carbonate affords the expected 1,2-disubstituted naphth[2,3-d]imidazole-4,9-diones (VI). The spectral properties of I, II, V and VI as well as those of some 2-acylamino-3-chloro-1,4-naphthoquinones IV are discussed. 相似文献
12.
Reactions of indoline (I), 2-methylindoline (II) and hexahydrocarbazole (III) with α,β-unsaturated acids in the presence of polyphosphoric acid have been investigated. Reaction of 1 with acrylic acid afforded two compounds which were identified as 1,2,4,5-tetrahydro-6H-pyrrolo-[3,2,1-ij] quinolin-6-one (IV) and 2,3,5,6,9,10-hcxahydro-1H-cyclopenta[f lpyrrolo [3,2,1-ij|-quinoline-1,8-dione (VII). The reaction oi 1 with crotonic acid gave compounds V and VIII, analogous-to IV and VII. The reaction of II with acrylic acid yielded two compounds VI and IX, whereas with crotonic acid, only X was isolated. With 111, acrylic acid afforded 5,6,8,9,10. 11,8a,11a-octahydro-4H-pyrido[3,2,1-jk]carbazol-4-one (XI) and a compound with a heretofore unknown ring system, viz., 2,3,5,6,7,8,11,12,5a,8a-decahydro-1H-cyclopenta[h] pyrido [3,2,1-jk |earbazole-1,10-dione. The structures of these compounds were deduced on the basis of their spectral and analytical data. 相似文献
13.
In contrast with the reaction of α-aminonitriles a, the corresponding -acylated α-aminonitriles b-f and oxalyl chloride do not yield pyrazinone derivatives, but 5-aminooxazoles - or 4(5)-imidazolones , the latter being converted in some cases into imidazo [2,1-]isoquinoline-2,5,6(3)-triones. Reactions of compounds b-f and ethyl chlorooxoacetate provide evidence for a 5(4)-iminooxazole intermediate , which aromatizes to yield 5-aminooxazoles -; however, unaromatizable īntermediates of type - isolable as 5(4)y-oxazolones after hydrolysis - undergo a catalyzed Dimroth-type rearrangement to give imidazolone derivatives . 相似文献
14.
Takehiko Nishio Katsuhiro Katahira Akira Kato Choji Kashima Yoshimori Omote 《Tetrahedron letters》1979,20(43):4211-4212
Irradiation of N-aryl-2(1H)-pyrimidin-2-ones (-) in a mixed benzene-alcohol solution afforded the products initiated by Type I cleavage, 1-(3-alkoxycarbonylamino-2-propene)-N-arylimines (-, , and ) in 45–51% yields. 相似文献
15.
Jochen Ellermann Adolf Veit Ekkehard Lindner Sigurd Hoehne 《Journal of organometallic chemistry》1983,252(2):153-174
The reaction of N(CH2CH2Cl)3 (I) with KAs(C6H5)2·dioxane () in THF yields, as Sacconi et al. reported earlier, 80% of N[CH2CH2As(C6H5)2]3 (II). II is now obtained in a still higher quantity from the reaction of [HN(CH2CH2Cl)3]Cl (III) with NaAs(C6H5)2 in liquid ammonia. Treatment of II with gaseous HI in dry CH2Cl2 results in the formation of [HN(CH2CH2AsI2)3]I (IV), which is isolated by recrystallisation from THF as [HN(CH2CH2AsI2)3]I · THF () (IVa). IVa reacts with H2O/NH3 or H2S/N(C2H5)3 to give the novel cryptands [N(CH2CH2)3]8-(As4O4)6 (V) or [N(CH2CH2)3]8(As4S4)6 (VI), which also can be denoted as spherands. The reaction of V with dry gaseous HCl in benzene leads to [HN(CH2-CH2AsCl2)3]Cl (VII). All the new compounds are characterized, as far as possible, by their IR, FIR, Raman, 1H NMR and mass spectra. To determine the structure of V a single X-ray crystal study was carried out. Moreover II, which is already well-known but not completely characterized, is included in this discussion only for spectroscopic comparison. 相似文献
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The photochemical addition of CF3I to buta-1,3-diene and vinylacetylene in the gas phase gave 1,4-adducts as the main products. In gas phase reactions only products derived from hydrogen abstraction were detected in the CF3I/penta-1,3-diene system, but the 1,4-adducts again predominated in the liquid phase. CCl3Br similarly gave a mixture of 1,2- and 1,4-adducts, the latter predominating, on photochemical reaction with penta-1,3-diene. The 1,2-adduct was the main product from the CCl3Br/pent-1-en-4-yn reaction, but some hydrogen abstraction was observed. The preference shown by conjugated dienes to give 1,4-adducts in the - configuration is interpreted in terms of steric factors and the propensity of dienes to adopt the - conformation. 相似文献
18.
Dodecahydro-8a-nitro--indacen-4 ( 2H )-one, dodecahy-dro-9a-nitro-4H-benz ¦e¦inden-4-one, dodecahydro-9b-nitro-5H-benz¦e¦inden-5-one and dodecahydro-4a-nitro-9 ( 1H )-phenanthrenone of -- backbone are synthesized in quantitative yield by cycloaddition reaction of 1-nitro-cyclopent-1-ene and 1-nitro-cyclohex-1-ene with 1-( cyclopenten-1-yl )- and 1-( cyclohexen-1-yl )-1-( piperidin-1-yl )-ethenes respectively. The enamine intermediates are also isolated and characterized. 相似文献
19.
Nmr and UV studies show that -dimethylamino--bromostyrene, I, undergoes SNl reaction in H2O and HClO4 (kSNl = 6 × 10?1sec.?1 at 25°). The vinyl cation has an extraordinary selectivity for capture by aromatic amines relative to H2O, including I itself to give the dimer II. 相似文献
20.
2-Hydroxybenzoic acid heated with 2,4 - bis(4 - methoxyphenyl) - 1,3,2,4 - dithiadiphosphetane - 2,4 -disulfide, 1, gave 2 - (p - methoxyphenyl) - 4 - 1,3,2 - benzoxathiaphosphorin - 4 - one 2 - sulfide, 3, and its thio-analogue, 4, while its ethyl or phenyl esters gave 4 as the sole product. 2 - Mercaptobenzoic acid and its ethyl ester when heated with 1 produced 3 - 1,2 - benzodithiole - 3 - one, 8, 3 -1,2 - benzodithiole - 3 - thione, 9, and 2- (p - methoxyphenyl) - 4 - 1,3,2 - benzodithia - phosphorin - 4 - one 2 - sulfide, 10. The reaction of 2 -aminobenzoic acid with 1 gave 1,2 - dihydro - 2 - (p - methoxyphenyl) - 4 - 3,1,2 - benzoxaphosphorin - 4 - one 2 - sulfide, 12. Reactions of 1 with methyl 2 - aminobenzoate and 2 - aminobenzamides are described. Mechanistic considerations for the formation of the heterocyclic phosphorus compounds are presented. 相似文献