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Simon J. Shaw 《合成通讯》2013,43(23):4183-4189
The treatment of benzocyclobutenol with a mild base has been investigated. This reaction results in an electrocyclic opening of the cyclobutene to the corresponding o‐quinodimethane, which has been successfully treated with aldehydes and electron‐deficient alkenes to form benzolactols and benzocyclohexenes respectively. 相似文献
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In situ generated nitro alkenes underwent tandem Michael-Henry and Michael-Michael sequences leading to the ‘one-pot’ formation of 3,4-substituted tetrahydrothiophenes using the commercially available 1,4-dithiane-2,5-diol (the dimer of mercaptoacetaldehyde) or its 4-mercapto-2-butenoates derivatives as suitable bifunctional partners, respectively. 相似文献
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Benjamin N. Bhawal Bill Morandi 《Angewandte Chemie (International ed. in English)》2019,58(30):10074-10103
Transfer hydrogenation, alkene metathesis, and alkyne metathesis possess great value to the synthetic chemistry community. One of the key features of these processes is their reversibility, which can be attributed to the presence of the same number and type of functional groups in both the reactants and products, making these reactions isofunctional. These classic reactions have recently inspired the development of novel shuttle and metathesis reactions that offer great promise for synthetic chemistry. This Review describes and systematically categorizes both recent and older examples of shuttle and metathesis reactions other than transfer hydrogenation and alkene/alkyne metathesis. 相似文献
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Edouard Godineau Dr. Yannick Landais Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(13):3044-3055
All in one pot! Radical, radical–ionic, and radical–organometallic MCR are highly convergent processes, representing a useful pathway to molecular and structural diversity (see scheme). This concept article highlights recent developments in the field and shows the potential of the strategy for the economical elaboration of various kinds of organic substrates.
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An efficient ‘one-pot’ synthesis of the title compounds based on a multicomponent domino reaction between imines and 3-nitro-1-propanol methanesulfonate has been developed. 相似文献
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Lawrence L. W. Cheung Andrei K. Yudin Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(13):4100-4109
In this contribution, aminocyclobutanes, as well as eight‐membered enamide rings, have been made from N‐vinyl β‐lactams. The eight‐membered products have been formed by a [3,3]‐sigmatropic rearrangement, whereas the aminocyclobutanes have been derived from a domino [3,3]‐rearrangement/6π‐electrocyclisation process. The aminocyclobutanes have been obtained in a highly diastereoselective fashion. The cyclobutane ring system tolerates fusion even if adjacent quaternary centres are present. Systems containing up to four fused rings are readily accessible. The reaction profile has been investigated by using Gaussian 03. This study suggests that two reaction pathways for aminocyclobutane formation are possible. In one pathway the [3,3]‐sigmatropic rearrangement is the rate‐limiting step and in the second pathway the electrocyclisation is rate limiting. Taken together, these reactions should facilitate the construction of fused heterocycles. 相似文献
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Yudong CaiBrian P Roberts 《Tetrahedron letters》2003,44(25):4645-4648
Terminal alkenes of the type H2CC(OR1)X, in which R1 is a tertiary alkyl or a 1-cyclopropylethyl group and X=Ph, OSiMe2But, OEt or H, undergo radical-chain reactions with organic halides R2Hal to give carbonyl compounds R2CH2C(O)X. 相似文献
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Carbopalladation Cascades Using Carbon–Carbon Triple Bonds: Recent Advances to Access Complex Scaffolds 下载免费PDF全文
Alexander Düfert Daniel B. Werz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16718-16732
Alkynes are one of the most versatile functional groups as synthetic handles. They allow for a direct access to partially or fully substituted alkenes through difunctionalization reactions. A prominently utilized transformation for these sequences is the carbopalladation of alkynes, which can be followed by various termination steps such as aromatizations, dearomatizations, cross‐coupling reactions, or pericyclic processes, amongst others. This Minireview provides an overview of the recent literature published in the field of carbopalladation chemistry, both with a focus on methodology as well as its application in the syntheses of complex molecular scaffolds, natural products, and functional molecules. 相似文献
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The dehydrobromination and debromination reactions of some α, β-dibromosulfones in a five-membered ring with sodium phenylthiolate, pyridine, and sodium methoxide have been studied. In general, phenylthiolate induces debromination elimination reactions while pyridine and methoxide induce dehydrobromination reactions. 相似文献
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H. Martin 《Angewandte Chemie (International ed. in English)》1966,5(1):78-84
Some recent examples of reactions proceeding both in the gas phase and in solution have been investigated to determine their kinetics and mechanisms. The ratio of the corresponding rate constants, kG and kL, of the elementary processes studied has been found to be about unity for unimolecular reactions and between 1 and 10 for bimolecular reactions. The mechanisms, overall rates, rate constants, and activation energies have been determined for the homogeneous gas reaction NOCl + Cl2O = NO2Cl + Cl2 and the reaction NOCl + N2O5 = NO2Cl + 2 NO2, carried out in C2F3Cl3. 相似文献
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von Wangelin AJ Neumann H Gördes D Klaus S Strübing D Beller M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(18):4286-4294
The acid-catalyzed condensation chemistry of simple amides and aldehydes provides a highly prolific source of diverse reactants for irreversible follow-up reactions. Amide-aldehyde mixtures have been successfully employed in multicomponent syntheses of N-acyl alpha-amino acids (via palladium-catalyzed amidocarbonylation) and various cyclohexene, cyclohexadiene, and benzene derivatives (via the amide-aldehyde-dienophile (AAD) reaction). 相似文献
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Olalla Nieto Faza Dr. Carlos Silva López Dr. Rosana Álvarez Dr. Ángel R. de Lera Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(8):1944-1956
Competition : The electrocyclizations of 1‐ and 3‐hydroxyheptatrienyl cations (see scheme) have been computationally studied at the B3LYP/6‐311G(d) level. The 1‐hydroxy system clearly favors a 4e? over a 6e? process, while for the 3‐hydroxy isomer these mechanisms compete.
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Dr. Silvia Garbarino Dr. Davide Ravelli Dr. Stefano Protti Prof. Andrea Basso 《Angewandte Chemie (International ed. in English)》2016,55(50):15476-15484
The combination of multicomponent approaches with light‐driven processes opens up new scenarios in the area of synthetic organic chemistry, where the need for sustainable, atom‐ and energy‐efficient reactions is increasingly urgent. Photoinduced multicomponent reactions are still in their infancy, but significant developments in this area are expected in the near future. 相似文献
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<正>Acetonylacetone 1 was treated with thiourea,aniline,glycine and glutamic acid to give pyrrole derivatives 2,3,5,and 9 by Paal-Knorr reaction,respectively.Then 3 was successfully transformed into the related pyrrole derivative 4 by Mannich reaction. Compounds 6,7 and 8 were obtained by reacting 5 with phenethyl alcohol,phenylallylic alcohol and leaf alcohol by esterification reactions,respectively.The structures of all new products were elucidated by IR,NMR and HRMS spectra. 相似文献
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The Morita-Baylis-Hillman reaction of cyclohexenone and p-nitro benzaldehyde is catalyzed by carrier proteins such as serum albumins or enzymes such as certain lipases, conversion of up to 35% and enantioselectivities of up to 19% being observed. 相似文献