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11.
The primary amino group of 3-(2-aminoethyl)-3-(4-chlorophenyl)-2,3-dihydro-1H-isoindol-1-one ( 1 ) was acylated with acetyl chloride, benzoyl chloride and phenyl acetyl chloride to form the amides 2a -c, respectively. These were cyclized in phosphorus oxychloride to give the 1-substituted-4a-(4-chlorophenyl)-4,4a-dihydropyrimido [6,1-a]isoindol-9(3H)-ones 3a-c . Heating of 1 in formic acid lead to the formation of 4a-(4-chlorophenyl)-4,4a-dihydropyrimido[6,1-a]isoindol-9(3H) -one (3d) . Heating of 1 in the presence of phosgene lead to the formation of 4a-(4-chlorophenyl)-2,3,4,4a-tetrahydropyrimido[6,1-a]isoindole-1, 9-dione (4). 相似文献
12.
Henri-Edouard Audier Marcel Fetizon Yannik Henry Thierry Prange 《Journal of mass spectrometry : JMS》1976,11(10):1047-1055
The fragmentation mechanisms of oxazole have been studied in detail on using various experimental techniques (refocusing of metastable ions, deuteration, AP measurements) and by theoretical calculations. 相似文献
13.
The temperature dependence of the 35Cl nuclear quadrupole resonance spectra of tetrachloro-o-benzoquinone (TOB) is reported. An analysis of the change in line multiplicities suggests that TOB undergoes three phase changes in going from 77 to 330 K. The transition temperatures have been determined. 相似文献
14.
Mohamed Boumerzoug Marcel Boudreau Peter Mascher 《Plasma Chemistry and Plasma Processing》1997,17(2):181-192
Real-time optical emission spectroscopy (OES) was used to monitor the deposition of TiN both from mixtures of tetrakis(dimethylamino)titanium
(TDMATi)-N2 and TiCl4-H2-N2 in an electron cyclotron resonance chemical vapor deposition system. The accurate control of the ratio of the emission intensities
of ionized nitrogen at 391.4 nm and molecular nitrogen at 357.7 nm (N
2
+
/N2) led to low temperature deposition of stoichiometric TiN (Ti/N ≈ 1) and very low resistivity in both cases. It was found
that high ion density plasmas are crucial for a considerable reduction of the deposition temperature while maintaining good
film quality. OES shows that the abundance of certain excited plasma species is not only dependent on the gas mixture and
the deposition parameters, such as total pressure and microwave power, but also is strongly affected by the magnetic field
configuration. The deposition rate and the film resistivity can be related to the emission intensity ratio, I(N
2
+
)/I(N2). Finally, the two processes are compared in terms of the quality of as-deposited and heat-treated films. The comparison
shows that the films obtained with TDMATi exhibit lower resistivity and are thermally more stable than with TiCl4. 相似文献
15.
José M. Bartoloméa Jesús AlcázarJ.Ignacio Andrés Marcel De BruynJavier Fernández Encarna MatesanzKristof Van Emelen 《Tetrahedron letters》2003,44(47):8545-8548
The synthesis of a series of novel analogues of the 3-substituted-2,3-dihydro-1,4-dioxino[2,3-b]pyridine core, modified in the non-aromatic ring, is described. Due to the presence of a versatile hydroxymethyl group in their structure, these novel scaffolds are attractive intermediates for the preparation of potential new therapeutic agents. 相似文献
16.
Maurice Prost Marcel Urbain Andr Schumer Christian Houben Clment Van Meerbeeck 《Helvetica chimica acta》1975,58(1):40-49
The authors describe the synthesis of decahydro-4-quinolinones and N-substituted 4-alkynyl-, 4-allyl- and 4-alkyldecahydro-4-quinolinols and discuss the stereochemical problems of this compounds. 相似文献
17.
The two isomeric tris(trichlorothienyl)carbinols have been synthesized. Upon treatment with acid the tris(trichlorothienyl)carbenium ions were formed, which upon reduction with iodide gave the tris(trichlorothienyl)methyl radicals, which were studied by epr-spectroscopy. The β-isomer, the tris(2,4,5-trichloro-3-thienyl)methyl radical, was much more stable than the α-isomer and showed great similarity to the perchlorotrityl radical. 相似文献
18.
Joëlle Mayrargue Michel Duchon D'Engenires Marcel Miocque 《Journal of heterocyclic chemistry》1978,15(2):263-267
By cyclization in aqueous media, 2-aminomethyl 1-alcynyl 1-cyclohexanols lead to perhydroisoindolinium or perhydroisoquinolinium salts. The stereochemistry of isolated diastereoisomers is elucidated. A stereoselectivity favouring trans junction of the rings is pointed out. 相似文献
19.
par Jean-michel Vierfohd Yvette Mettey Line Mascrier-Demagny Marcel Miocque 《Tetrahedron letters》1981,22(13):1219-1222
An original one-pot ayntheais of 4,7-diazaindoles is achieved by metalation of methylpyrazines or methylquinoxaline wich are then condensed with an aromatic nitrile: an intermediate imine-enamine is formed which leads, by intramolecular cyclization, to diazaindoles. 相似文献
20.
The present paper deals with the experimental and theoretical determination of energies of conjugation of organic molecules.A computation process has been applied, first to simple molecules comprising an hydrocarbon (styrene), an oxygen function (benzaldehyde) and a nitrogen function (aniline). The results are compared with those obtained from the literature.The application of this computation process to naphthoic acids permits the determination of energies of conjugation and isomerization of these molecules. 相似文献