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Adam Morel et al.
Dalton transactions (Cambridge, England : 2003), 42(4), 1215-1222 (2012-11-09)
Chiral ionic liquids (CILs) containing L-prolinate and L-lactate anions and non-chiral quaternary ammonium cations were employed in the palladium catalyzed enantioselective Heck arylation of 2,3-dihydrofuran with aryl iodides (iodobenzene, 4-iodotoluene, 2-iodoanisole, 4-iodoanisole, 4-iodoacetophenone). In all the reactions 2-aryl-2,3-dihydrofuran (3) was
Clay M Horiuchi et al.
Langmuir : the ACS journal of surfaces and colloids, 26(16), 13320-13332 (2010-08-11)
High-resolution electron energy loss spectroscopy (HREELS) and temperature-programmed desorption (TPD) were used to study the adsorption and thermal chemistry of 2,3-dihydrofuran (2,3-DHF) and 2,5-dihydrofuran (2,5-DHF) on Pd(111). The results, paired with earlier computational results, indicate that 2,3-DHF and 2,5-DHF both
Timothy J Donohoe et al.
Organic letters, 9(6), 953-956 (2007-02-24)
The enol ether-olefin ring-closing metathesis reaction has been employed to generate 2,3-dihydrofurans that are equipped with a leaving group. These substrates are at the correct oxidation state to undergo an acid-catalyzed aromatization, and this strategy has been utilized to provide
The Journal of Organic Chemistry, 59, 4535-4535 (1994)
Sandro Cacchi et al.
Organic & biomolecular chemistry, 9(24), 8233-8236 (2011-11-02)
The palladium-catalyzed reaction of (hetero)aryl bromides, chlorides, and nonaflates with α-allyl-β-ketoesters provides ready efficient access to functionalized 2,3-dihydrofurans. The reaction tolerates several useful substituents including chloro, fluoro, ether, ketone, ester, cyano, and nitro groups.
Rui Zhang et al.
The Journal of organic chemistry, 73(20), 8089-8092 (2008-09-19)
A convenient and efficient synthesis of substituted dihydrofurans is developed via ring-enlargement of 1-dimethylaminopropenoyl-1-carbamoyl/benzoyl cyclopropanes catalyzed by ammonium acetate in acetic acid with high regio- and stereoselectivity. Some of the newly synthesized substituted dihydrofurans are subjected to further synthetic transformation
Qi-Fang Wang et al.
The Journal of organic chemistry, 74(19), 7403-7406 (2009-09-11)
An efficient synthetic procedure for the preparation of fused 2,3-dihydrofuran derivatives was developed with the assistance of pyridinium ylide. A sequential one-pot, two-step tandem reaction starting from pyridine, aromatic aldehyde, dimedone, or 4-hydroxycoumarin and alpha-phenacyl bromide or p-nitrobenzyl bromide with
Tetrahedron, 50, 4557-4557 (1994)
Javier Mazuela et al.
Organic & biomolecular chemistry, 9(3), 941-946 (2010-12-15)
We describe the application of a new class of ligands--the phosphite-oxazole/imidazole (L1-L5a-g)--in asymmetric intermolecular Pd-catalyzed Heck reactions under thermal and microwave conditions. These ligands combine the advantages of the oxazole/imidazole moiety with those of the phosphite moiety: they are more
Synlett, 431-431 (1994)
Lun-Zhi Dai et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 14(23), 7011-7018 (2008-07-08)
The gold(I)-catalyzed cycloisomerization of epoxy alkynes in the presence of a nucleophile is an efficient protocol to provide ketal skeletons with high stereoselectivity. An intramolecular reaction of propargylic/homopropargylic alcohols with oxirane to produce ketal/spiroketals in moderate yields under mild conditions
Raúl Pérez-Ruiz et al.
Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology, 5(1), 51-55 (2006-01-06)
The bicyclic oxetanes and resulting from photocycloaddition of aromatic aldehydes to 2,3-dihydrofuran, were efficiently cleaved by means of electron-transfer reduction, photoinduced by the electronically excited reductants 1-methoxynaphthalene (MN) and 2,7-dimethoxynaphthalene (DMN) in acetonitrile. The fluorescence quenching rates of DMN/MN by
Peizhong Xie et al.
Chemistry, an Asian journal, 7(7), 1533-1537 (2012-04-19)
A new domino reaction for Nazarov reagents: An efficient approach was developed for the construction of highly functionalized conjugated 2,3-dihydrofuran skeletons. Nazarov reagents were used for the first time in a phosphine-catalyzed domino reaction and successfully used to construct five-membered
Claudia G Cobo-Angel et al.
Scientific reports, 9(1), 14025-14025 (2019-10-03)
Group B Streptococcus (GBS), is a leading cause of neonatal death and an emerging pathogen in adults. Additionally, GBS is a bovine pathogen causing intramammary infections. The likelihood of GBS interspecies transmission is largely unknown. We explored the potential transmission
Angela M Bernard et al.
Organic letters, 7(21), 4565-4568 (2005-10-08)
[reactions: see text] Regioselective synthesis of 2,4,5- or 3,4,5-trisubstituted 2,3-dihydrofurans has been realized by using donor-acceptor cyclopropanes or by a Corey ylide reaction with alpha-sulfenyl-, alpha-sulfinyl-, or alpha-sulfonylenones. The method allowed a straightforward synthesis of the natural product calyxolane B.
H J Jørgensen et al.
Veterinary microbiology, 184, 64-72 (2016-02-09)
Many free-stall bovine dairy herds in Norway fail to eradicate Streptococcus agalactiae despite long-term control measures. In a longitudinal study of 4 free-stall herds with automatic milking systems (AMS), milk and extramammary sites were sampled 4 times with 1-2 month
Gang Zhou et al.
Journal of the American Chemical Society, 127(34), 11958-11959 (2005-08-25)
A highly enantioselective [3+2]-cycloaddition reaction of 2,3-dihydrofuran with 1,4-benzoquinones using a chiral oxazaborolidinium triflimidate as catalyst has been developed which allows rapid access to a variety of chiral phenolic tricycles (enantiomeric excesses ranging from 91 to 98%). The utility of
Z Szendi et al.
Steroids, 56(9), 458-463 (1991-09-01)
Pregnenolone 3-(2'-tetrahydropyranyl) ether (1) was condensed with 3,4-[2H]dihydropyran to mainly give (20R)-[6'-(3',4'-[2'H]dihydropyranyl)]-pregn-5-ene-3 beta,20-diol 3-(2'-tetrahydropyranyl) ether (20R-3), according to nuclear magnetic resonance (NMR). Cold, dilute HCl in ethanol removed the tetrahydropyranyl group at C-3 and also opened the dihydropyranyl ring at
Wen-Qiong Wu et al.
Journal of the American Chemical Society, 130(30), 9717-9725 (2008-07-02)
A series of benzylic substituted P, N-ligands 1 and 2 have been synthesized. The Pd-complexes of these ligands show high catalytic activity and enantioselectivity in catalyzing the asymmetric Heck reaction. A dramatic switch in enantioselectivity is realized using ligands with
An integrated microreactor system for self-optimization of a Heck reaction: from micro- to mesoscale flow systems.
Jonathan P McMullen et al.
Angewandte Chemie (International ed. in English), 49(39), 7076-7080 (2010-08-21)
Montserrat Dieguez et al.
Chemical communications (Cambridge, England), (9)(9), 1221-1223 (2005-02-24)
Good enantioselectivities and excellent regioselectivities are achieved in the Rh-catalyzed asymmetric hydroformylation of 2,5- and 2,3-dihydrofuran using diphosphite ligands; whereby the backbone of the ligand is crucial to suppressing isomerization and obtaining high ee's.
Copper-catalyzed asymmetric [4+1] cycloadditions of enones with diazo compounds to form dihydrofurans.
Sunghee Son et al.
Journal of the American Chemical Society, 129(5), 1046-1047 (2007-02-01)
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