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Sulfonimines derived from aryl and nonenolizable aliphatic aldehydes can be effectively allylated to the corresponding homoallylic sulfonamides with allylic bromides promoted by indium or zinc. The solvent used can be water, THF, or a mixed aqueous THF solvent. The regioselectivity and stereoselectivity of the reaction were studied. 相似文献
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锌和锡参与下末端环氧化物的选择性烯丙基化反应 总被引:1,自引:0,他引:1
烯丙基溴和金属辛或锡成功地将末端环氧化合物1一锅法合成高烯丙基醇2和双高烯丙基醇3. 还研究了环氧化合物取代基的影响, 并提出了此烯丙基化的反应途径 . 相似文献
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Wet silica gel promotes the chemoselective and almost complete allylation of aldehydes with 0.25-0.30 molar equivalents of tetraallyltin without an organic solvent, leaving no organotin compounds, requiring neither extraction nor chromatographic separation after the reaction, and enabling the repeated use of the silica gel. 相似文献
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Suguru Ito 《Tetrahedron letters》2009,50(24):2967-930
Mesoporous aluminosilicate (Al-MCM-41) was found to catalyze the allylation of both aromatic and aliphatic aldehydes with allylsilanes although amorphous silica-alumina or mesoporous silicates (MCM-41, SBA-15) could not catalyze the reaction under the same reaction conditions. The solid acid catalyst Al-MCM-41 could be reused three times without significant loss of activity. 相似文献
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A highly stereoselective approach to tetrasubstituted (E)-β-hydroxy silyl enol ethers is described. The reaction proceeds via a sequential addition/[1,2]-Brook rearrangement/epoxide-opening process of aryl-substituted oxiranyl anions with acylsilanes. 相似文献
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Masayuki Kirihara Takuya Noguchi Hiroko Kakuda Akihiro Shimajiri Akihiko Hatano 《Tetrahedron letters》2006,47(22):3777-3780
The reaction of tertiary cyclopropyl silyl ethers with diethylaminosulfur trifluoride in electron-rich aromatic compounds causes the Friedel-Crafts alkylation to produce allylated or cyclopropylated aromatic compounds. 相似文献
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Iron trichloride hexahydrate has proved to be a very effective catalyst for the three‐component condensation of aromatic aldehydes, amines and allyltributylstannane, which produces high yields of homoallylic amines in water in the presence of surfactant SDS. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Junyan Ma Danfeng Huang Ke‐Hu Wang Yanli Xu Siying Chong Yingpeng Su Ying Fu Yulai Hu 《应用有机金属化学》2016,30(7):571-576
An efficient process for the synthesis of homoallylic amines and N′‐homoallylic hydrazides is developed from the one‐pot reaction of carbonyl compounds, amines or N‐acylhydrazines, allyllic bromide and tin powder using water as solvent. N‐Acylhydrazines are found to be more reactive than amines in these processes. They can react not only with aldehydes but also with ketones to give the corresponding N′‐homoallylic hydrazides. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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An enantioselective indium-mediated allylation reaction of aldehydes and ketones in dichloromethane 总被引:1,自引:0,他引:1
An enantioselective indium-mediated addition reaction of allylic bromides to carbonyl compounds was achieved in dichloromethane in the presence of (−)-cinchonidine. The desired products were obtained in moderate to excellent yields and with up to 75% enantioselectivity. 相似文献
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The O‐allylation of bisphenol A (BPA) has been performed with the most selective catalysts for O‐allylation of phenols reported previously. Both the cyclopentadienyl–ruthenium catalysts and the palladium–diphosphine catalysts are capable of selectively performing single and double O‐allylation of BPA. An intriguing solvent effect is observed; the choice of the solvent is of key importance for both conversion and selectivity. The use of an excess of diallyl ether as allylating agent results in relatively high yields of the bisallyl ether of bisphenol A, while maintaining the high selectivity for O‐allylation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Silvana C NgoWoo Jin Chung Dong Sung LimSeiichiro Higashiya John T Welch 《Journal of fluorine chemistry》2002,117(2):207-211
The reactions of difluoroacetyltrialkylsilanes with methylidene triphenylphosphorane and benzylidene triphenylphosphorane are affected by the nature of the silyl substituents giving either the enol silyl ether or normal Wittig product exclusively, or mixture of both. Reactions with Horner-Emmons type ylide gave only the alkene products. Reactions of mono- and difluoroacetyltrialkylsilanes with dimethylsulfoxonium methylide gave the enol silyl ether products exclusively. Conversion of an enol silyl ether to an epoxide was effected with m-CPBA. 相似文献
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Suguru ItoAkira Hayashi Hirotomo KomaiHitoshi Yamaguchi Yoshihiro KubotaMasatoshi Asami 《Tetrahedron》2011,67(11):2081-2089
A mesoporous aluminosilicate (Al-MCM-41) was found to be an effective heterogeneous catalyst for the reaction of both carbonyl compounds and acetals with allylsilanes to afford the corresponding homoallyl silyl ethers and homoallyl alkyl ethers, respectively. Both the mesoporous structure and the presence of aluminum moiety were indispensable for the high catalytic activity of Al-MCM-41. Moreover, Al-MCM-41 could catalyze the reaction of acetals chemoselectively in the presence of the corresponding carbonyl compounds. The solid acid catalyst Al-MCM-41 could be recovered easily by filtration and could be reused three times without a significant loss of catalytic activity. 相似文献
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