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951.
A series of 3-(N-substituted)-aminoquinolin-2(1H)-ones have been synthesized by the palladium-catalyzed C-N coupling reaction starting from 3-bromoquinolin-2-(1H)-ones. Various nucleophiles including amines, amides, sulfonamides, carbamates and ureas have been used successfully. In all the cases, the reactions take place rapidly in 1,4-dioxane and proceed in good to excellent yield using palladium acetate as a catalyst, Xantphos as a ligand and Cs2CO3 as a base. 相似文献
952.
Wei Zhang 《Tetrahedron》2007,63(43):10569-10575
CH2ClF has been found to be a useful electrophilic monofluoromethylating agent for a variety of O-, S-, and N-nucleophiles. The reaction is not sensitive to the radical scavenger such as nitrobenzene, which strongly supports an SN2 mechanism rather than an SET mechanism. Although most of these products (fluoromethyl ethers, sulfides, and amines) can be isolated with good purity, some of these compounds do intend to decompose (via defluorination) during storage. The electrophilic monofluoromethylation of carbon-nucleophiles was attempted with CH2ClF, CH2FI, or FCH2OTs as monofluoromethylating agents, but with no success. 相似文献
953.
954.
V. M. Lyubchanskaya E. K. Panisheva S. A. Savina L. M. Alekseeva A. S. Shashkov V. G. Granik 《Russian Chemical Bulletin》2005,54(7):1690-1699
The Nenitzescu reaction involving quinoneimines was studied; new 5-aminoindole, 5-aminobenzofuran, and 9-aminochromenopyridine
derivatives were synthesized.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1640–1649, July, 2005. 相似文献
955.
An innovative route for the synthesis of substituted dibenzofurans has been delineated through a ring transformation reaction of suitably functionalized 2H-pyran-2-ones by reaction with 7-methoxybenzofuran-3-one, in high yield. The novelty of the procedure lies in the creation of an aromatic ring from a 2H-pyran-2-one involving the -COCH2-moiety of the substrate. 相似文献
956.
Pelayo Camps 《Tetrahedron》2004,60(25):5423-5431
Two diastereomeric pairs of rationally designed huprines additionally substituted at position 13 with a formamido or an acetamido group have been synthesized as potential high affinity acetylcholinesterase inhibitors. The synthetic sequence involves hydrolysis of two diastereomeric 13-methanesulfonamido-huprines, followed by acylation of the resulting diastereomeric amines. In the hydrolysis reaction, carried out with PPA under harsh conditions, significant amounts of cyclized or rearranged by-products were also formed, depending on the stereochemistry of the starting compound. 相似文献
957.
Amidrazone 1a and the tricarbonyl derivatives 2b-d reacted in boiling ethanol in the presence of 2,5-norbornadiene 5 giving the pyridine derivatives 6b-d respectively (59-72%) and in the presence of 2,3-dihydrofuran 7 yielding the lactones 10b-d (39-44%). The 2,2′-bipyridine derivatives 6e-g were similarly obtained in good yield (81-87%) from the reaction of amidrazone 1b and tricarbonyl derivatives 2b-d in the presence of 2,5-norbornadiene 5. 相似文献
958.
Itaru Nakamura 《Tetrahedron letters》2004,45(14):2903-2906
Ytterbium-catalyzed tandem carboalkoxylation/Friedel-Crafts reaction of arylidenecyclopropanes 1 with acetals 2 afforded the corresponding indene derivatives 3 in good to high yields. For example, in the presence of 10 mol % of Yb(OTf)3 the reaction of 1-phenylbenzylidenecyclopropane 1a with the dimethyl acetals of benzaldehyde 2a, p-tolualdehyde 2b, and p-anisaldehyde 2c gave 1,3-diphenyl-2-(2-methoxyethyl)indene 3a, 2-(2-methoxyethyl)-3-phenyl-1-(p-tolyl)indene 3b, and 1-(p-anisyl)-2-(2-methoxyethyl)-3-phenylindene 3c in 82%, 80%, and 80% yields, respectively. 相似文献
959.
960.