共查询到20条相似文献,搜索用时 15 毫秒
1.
Aldol Condensation of β-Diketones and β-Ketoesters with Aldehydes Catalyzed by Samarium (III) Iodide
Catalyzed by SmI3 β-diketones and β-ketoesters condense with aldehydes to give benzylidene substituted β-diketones and β-ketoesters at room temperatures in fair yields. 相似文献
2.
Study of Activation and Inhibition of Certain Metal Ions to Amylase Catalyzed Reaction by Microcalorimetry 总被引:1,自引:0,他引:1
IntroductionMostcomplicatedreactionshappenedinlivingcrea tures ,amongthemenzymecatalyzedreactionisanimpor tantclass .Itissignificantinboththeoryandpracticetoinvestigateenzymecatalyzedreaction .Therearemanyex perimentalmethodssuchasspectrophotometry ,titrimetry ,isotopemethod ,microcalorimetryandsoon ,inwhichmi crocalorimetryisanewoneduetoitshighsensitivityandaccuracy .Wecanstudythewholeprocessoftheheatef fectusingamicrocalorimeter .Sincetheabsorptionorpro ductionofheatisanintrinsicpropertyofe… 相似文献
3.
Orazio A. Attanasi Paolino Filippone Amedeo Mei Francesca Romana Perrulli Franco Serra-zanetti 《合成通讯》2013,43(11):1411-1421
Pyrrole and several its derivatives have been subjected to extensive chemical investigations, while substituted 1-aminopyrroles remain a class of compounds about which relatively little is known due to the far from trivial problem sposed by their syntheis. In fact, 1-aminopyrroles appear to be prepared mainly by direct reactionfrom conjugated azoalkenes,2 that unfortunately represent a class of relatively little 相似文献
4.
Andrea Preuß Marcus Korb Tobias Rüffer Jörn Bankwitz Colin Georgi Alexander Jakob Stefan E. Schulz Heinrich Lang 《无机化学与普通化学杂志》2020,646(13):670-680
The template synthesis of ethylenediamine ( 1 ) with 2-acetylcyclopentanone ( 2 ) and [Cu(OAc)2 · H2O] ( 5 ) produced [Cu(1-(2-cC5H6(O))C(Me)NCH2)2)] ( 6 ) in 82 % yield. Reaction of 5 with bis(benzoylacetone)diethylenetriamine ( 7 , = L H)[1] gave [Cu(μ-OAc)( L )(H2O)]2 ( 8 ). The solid-state structures of 6 and 8 were determined confirming that 8 possesses intra- and intermolecular hydrogen bonds resulting in a dimer formation. The thermal behavior of 6 – 8 was studied by TG and TG-MS. Under oxygen CuO was formed, whereas under Ar Cu/Cu2O ( 6 ) or Cu ( 8 ) was obtained. Complex 6 was used as CVD precursor for Cu and Cu-oxide deposition (substrate temp., 400–500 °C, N2, 60 mL · min–1; O2, 60 mL · min–1; pressure, 0.87–1.5 mbar). The as-obtained deposits show separated particles of different appearance at the substrate surface as evidenced by SEM. Non-volatile 8 was applied as spin-coating precursor for Cu and CuO formation [conc. 0.25 mol · L–1; volume 0.2 mL; 3000 rpm; depos. time 2 min; heating rate 50 K · min–1; holding time 60 min (Ar), 120 min (air) at 800 °C]. The samples on silicon consist of granulated particles (Ar) or are non-dense with a grainy topography (air). EDX and XPS measurements confirmed the formation of Cu (Ar) or CuO (O2) with up to 13 mol-% C impurity. 相似文献
5.
Palladium chloride–catalyzed Suzuki cross‐coupling reaction was applied to the preparation of highly pure multiring liquid crystals with a biphenyl unit. The optimal reaction condition is the combination of 0.5 mol% PdCl2, pyridine, and K3PO4, which was able to catalyze the cross‐coupling of substituted aryl bromides with substituted trans‐cyclohexylphenylboronic acids to give pure products in 38–87% yields. 相似文献
6.
A novel procedure for the preparation of organic ammonium tribromides (OATBs) is described from their corresponding bromides. Quaternary ammonium bromides (QABs) and a N,N′-heterocyclic dibromide are efficiently oxidized to their corresponding monotribromides and bistribromide by m-chloroperbenzoic acid (MCPBA) in the presence of 2 and 4 equiv of KBr, respectively. The reactions are carried out in an aqueous medium without the use of any mineral acid or metal catalyst/promoters. A variety of tribromides are synthesized in very good yields including a hitherto unknown reagent, 1,10-(ethane-1, 2-diyl)phenanthrolinediium bistribromide (EPDBT). EPDBT is investigated as brominating agent and found to be highly effective for selective bromination of active methylene groups of a variety of 1,3-diketones and β-ketoesters. 相似文献
7.
Cyclization of alkynyl ketones with β-ketoesters mediated by PPh3 and KOBut to synthesize 2-pyrone derivatives was systematically described. A variety of β-ketoesters reacted with alkynyl ketones to give functionalized 2-pyrones in moderate to good yields under mild conditions. 相似文献
8.
The reaction of diaryliodonium salts with β-substituted-α,β-enones in the presence of a palladium catalyst affords Hβ-substituted products with excellent yields. 相似文献
9.
α,β-Unsaturated nitriles were synthesized from the iodine catalyzed reaction of chloro-acetonitrile with aldehydes promoted by tri-n-butylarsine and magnesium. 相似文献
10.
Ce(IV) as ceric ammonium nitrate can effectively catalyze ring opening of epoxides with halides under very mild conditions and easy procedure to give the corresponding β-chloro-and β-bromohydrins in excellent yields. The reactions occur with both substituted and unsubstituted quaternary ammonium halides and with high regio- and stereoselectivity. The reaction of optically active styrene oxide with chloride ion was found to be highly stereospecific and afforded the corresponding β-halohydrin in 96% ee. 相似文献
11.
LI Yana b WU A-Qinga b ZHENG Fa-Kuna② GUO Guo-Conga② LU Can-Zhonga HUANG Jin-Shuna a 《结构化学》2005,(11)
1 INTRODUCTION Exploration on the syntheses and properties of car- boxylate complexes, especially aromatic carboxylate complexes, has always been a fascinating and chal- lenging research field for decades either in coor- dination chemistry or in functional materials[1, 2]. Cy- anobenzoic acid (Hcba) possessing two functional coordination groups should display structural diver- sities on the formation of complexes[3~15]. In particu- lar, the copper(II) carboxylate complexes bearing spe- … 相似文献
12.
Reaction of β-cyclodextrin (β-CD) with CuCl2 in neutral aqueous solutions gave a stable molecular complex without any side-arm support. The X-ray crystallographic analysis clarified that the copper ion was located at the bottom of the primary-hydroxy side as a CuCl2(H2O)2 form. Hydrogen bonds were found between the Cl and H2O ligands and β-CD hydroxy and ether groups. The copper ion is axially coordinated with a hydroxy group of a neighboring β-CD molecule, giving a one-dimensional β-CD/CuCl2 array. 相似文献
13.
Doan Pham Minh Ange Nzihou Patrick Sharrock Jocelyn Ramaroson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1132-1140
Abstract Direct synthesis of sodium cyclotriphosphate, Na3P3O9 (SCTP), from sodium chloride and orthophosphoric acid as economical starting materials was investigated. Reaction conditions including the heating rate, reaction plateau time, air flow rate, and Na/P molar ratio were found to be key parameters for the elimination of chloride and for the selectivity in SCTP. High yields in SCTP (94–99%) were obtained. The results are very interesting with respect to a potential industrial application for the synthesis of SCTP from point of view of the low cost of the starting materials. 相似文献
14.
15.
《Polyhedron》1988,7(21):2233-2234
Nickel(II) acetylacetonate or benzoylacetonate on treatment with hydroxylamine at O°C give adducts of the type Ni(β-diket)2(NH2OH) 2 which on heating in refluxing ethanol afford β-ketooximato complexes of the type Ni(β-ketox)2(H2O)2. 相似文献
16.
Hong Xia BI Chang Wei MA 《中国化学快报》2006,17(8):1041-1044
It was reported that3-methylbutanal was an important volatile compound in dry-cured ham products1-3.It has been associated with nutty,cheesy and salty notes in Parma ham4and correlated with the aged flavor of hams5.It is also maybe one of the reasons for … 相似文献
17.
SA (sulfamic acid) catalyzes the reaction of indole with aldehyde and ketone to afford bis(indol-3-yl)methanes in good to excellent yields under solvent-free condition at ambient temperature. 相似文献
18.
Waldemar Adam Chantu R. Saha-M?ller Oliver Weichold 《Monatshefte für Chemie / Chemical Monthly》2000,13(7):697-705
Optically active diastereomeric β-hydroperoxy esters 4 have been prepared by singlet oxygen ene reaction of β,γ-unsaturated esters 3 and subsequent horseradish peroxidase (HRP) catalyzed kinetic resolution of the ene product. The highest enantiomeric excess (up to 95%) has been obtained for the isopropyl ester threo-4c, which establishes that the size of the remote ester functionality exercises appreciable control in the enantioselectivity of the enzymatic kinetic resolution. 相似文献
19.
《Journal of fluorine chemistry》1988,38(2):257-262
3-SCF3 substituted 4-methyl-2(1H)-, 4-phenyl-2(1H)-, 2-methyl-4(1H), and 2-phenyl-4(1H)-quinolinones were obtained by cyclization of the respective -SCF3 submitted acetoacetanilides or benzoylacetanilides or their β-phenylimino analogues in concentrated sulphuric acid upon heating. The structures of the compounds obtained were elucidated by elemental analysis and their IR, 1H and 19F NMR, and mass spectra. 相似文献