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1.
Mercedes Blanco M. Gabriela Lorenzo Isabel Perillo Celia B. Schapira 《Journal of heterocyclic chemistry》1996,33(2):361-366
The reaction of N-substituted quinolinimides 1a-d with sodium alkoxides afforded a mixture of 1,6-naphthyridines 2 and 1,7-naphthyridines 3 which were isolated by chromatographic methods. Structure assignment for each pair of isomers was made by comparison of their 1H nmr spectra with those of picolinamide and nicotinamide. When esters 1a -c were treated with alkoxides from primary alcohols, other than that of the ester, total transesterification took place. Experimental results suggest that transesterification occurs in open intermediary species. 相似文献
2.
Roger L. Snowden Simon M. Linder Bernard L. Muller Karl H. Schulte-Elte 《Helvetica chimica acta》1987,70(7):1858-1878
The transformation of 36 bis(homoallylic) alcohols VII to alkenones IX and X via β-cleavage of their potassium alkoxides VIIa in HMPA has been investigated (cf. Scheme 2). These studies have established an order of β-cleavage for 2-propenyl, 1-methyl-2propenyl, 2-methyl-2-propenyl, 1,1-dimethyl-2propenyl, and benzyl groups in alkoxides 49a – 56a and have allowed a comparison between the β-cleavege reaction and the oxy-Cope rearrangement in alkoxides 74a – 83a . As illustrative syntheti applications, a two-step preparatio of propenyl ketones 15 – 42 from carboxylic esters is described, together with syntheses of ar-turmerone ( 48 ), α-damascone ((E)- 71 ), β-damascone ((E)- 109 ), and β-damascenone ((E)- 111 ). 相似文献
3.
EXAFS studies of primary zirconium alkoxides Zr(OR)4 with OR = n-propoxide and n-butoxide, dissolved in their corresponding alcohols and chemically modified with acetylacetone (Hacac) and acetic acid (HOAc)
in different molal ratios, are presented. The EXAFS-spectroscopic results, supported by FT-IR-studies, indicate a different
chemical behavior of the complexing agents. In contrast to acetylacetone, the addition of acetic acid does not change the
oligomeric structure of the zirconium alkoxides. Amazingly, the modification with acetic acid leads, in comparison to the
pure compounds, to a shortened metal centre distance, whereas in the reaction with acetylacetone the Zr-Zr distance is not
changed. With the determined distances and a rough quantitative inclusion of the coordination numbers it was possible to deduce
detailed structure models. 相似文献
4.
T. Hamaide R. Spitz J. P. Letourneux J. Clavene A. Guyot 《Macromolecular Symposia》1994,88(1):191-200
New heterogeneous catalysts for ring opening oligomerization are obtained by grafting alkyl aluminium moieties on silica. Adding alcohol in excess causes the formation of aluminium alkoxides and allows the catalytic mode, because of a rapid exchange reaction between the grafted active centers and the free alcohols present in the medium. All the polymer chains are end-capped by these alcohol molecules, which give functionalized oligomers. 相似文献
5.
Summary Novel bimetallic alkoxides of copper(II) of the type Cu[M(OPr-i)6]2 (M = Nb or Ta) have been synthesised by the interaction of CuCl2 (1 mol) with K[M(OPr-i)6] (2 mol). These bimetallic isopropoxides undergo facile alcohol interchange with primary alcohols such as MeOH, EtOH,n-PrOH andn-BuOH. However, witht-BuOH, the reaction cannot be driven to completion even under prolonged continuous azeotropic fractionation of the liberatedi-PrOH and the final product corresponded in analysis to Cu[Ta(OPr-i)2(OBu-t)4]2.I.r., electronic and electron spin resonance spectral and magnetic susceptibility measurements indicate a distorted octahedralD
4h geometry for copper(II) in these bimetallic alkoxides. 相似文献
6.
Sucheta Mondal Subhasree Pal Subhankar Khanra Santana Chakraborty Dr. Nanda D. Paul 《欧洲无机化学杂志》2023,26(29):e202300263
Herein we report a cobalt-catalyzed sustainable approach for C−N cross-coupling reaction between amines and alcohols. Using a well-defined Co-catalyst 1 a bearing 2-(phenyldiazenyl)-1,10-phenanthroline ligand, various N-alkylated amines were synthesized in good yields. 1 a efficiently alkylates diamines producing N, N′-dialkylated amines in good yields and showed excellent chemoselectivity when oleyl alcohol and β-citronellol, containing internal carbon-carbon double bond were used as alkylating agents. 1 a is equally compatible with synthesizing N-heterocycles via dehydrogenative coupling of amines and alcohols. 1H-Indole was synthesized via an intramolecular dehydrogenative N-alkylation reaction, and various substituted quinolines were synthesized by coupling of 2-aminobenzyl alcohol and secondary alcohols. A few control reactions and spectroscopic experiments were conducted to illuminate the plausible reaction mechanism, indicating that the 1 a -catalyzed N-alkylation proceeds through the borrowing hydrogen pathway. The coordinated arylazo ligand participates actively throughout the reaction; the hydrogen eliminated during dehydrogenation of alcohols was set aside in the ligand backbone and subsequently gets transferred in the reductive amination step to imine intermediates yielding N-alkylated amines. On the other hand, 1 a -catalyzed quinoline synthesis proceeds through dehydrogenation followed by successive C−C and C−N coupling steps forming H2O2 as a by-product under air. 相似文献
7.
A. Monge J. A. Palop T. Goí A. Martínez E. Fernndez-Alvarez 《Journal of heterocyclic chemistry》1985,22(5):1445-1451
The Vilsmeier-Haack reaction with ethyl 2-(1-methylindole)acetate and N,N-Dimethylamides/phosphorus oxychloride gave (65–85%) of ethyl 2-(3-acyl-1-methylindole)acetates 2 , which when boiled with hydrazine yielded about 90% of 4,5-dihydro-6-methyl-4-oxo-3H[1,2]diazepino[5,6-b]indoles 3. The attempted cyclization of 2-(1-methylindole)acetohydrazones 6 with acyl (acetyl and benzoyl) chlorides/triethylamine, to [1,2]diazepino[5,6-b]indole derivatives was fruitless and the bis(acyl)hydrazones 9 were obtained. Several transformations of 9 are reported. Similarly, the attempted cyclization of 3-indoleacetohydrazones 14 with acetyl chloride/triethylamine to [1,2]diazepino[4,5-b]indole derivatives was also fruitless and the bis(acyl)hydrazones 16 were again obtained. 相似文献
8.
Indole-3-carboxylic acid (as well as indole-3-glyoxylic acid) derivatives are readily prepared from indoles (including oxindoles) and phosgene (oxalyl chloride), respectively. The interaction of these reagents with the indole Grignard reagent afforded several products including the cyclo-tetramers, 21 and 30 . Indolo-fused heterocycles can be readily prepared from the reaction of phosgene (or oxalyl chloride) with suitable reactants. Thus e.g., phosgene and 2-(2-hydroxy-phenyl)-N-methylindole readily gave 5,6-dihydro-11-methyl-6-oxobenzo[a]pyrano[4,3-b] indole ( 33 ). 相似文献
9.
The thiocyanate cleavage of the Na-o-nitrophenylsulfenyl group from peptides in solution or on a solid support proceeds effectively in the presence of (2-methyl-1-indolyl)acetic acid. This scavenger was prepared from 2-methylindole and sodium bromoacetate; it can readily be removed by extraction with base after the cleavage reaction, together with (2-methyl-3-(2-nitrophenylthio)-1-indolyl)acetic acid. 相似文献
10.
《Tetrahedron: Asymmetry》1999,10(1):169-176
In the presence of equimolar amounts of lithium alkoxides derived from N-substituted 2-amino-1,2-diphenyl-ethanols, alkyllithium reagents add to benzaldehyde to furnish optically active secondary alcohols with enantiomeric excesses of up to 86%. The best results were obtained using the N-isopropyl-N-methyl substituted amino-alcohol. 相似文献
11.
Novel extremely oxygen sensitive (many pyrophoric) alkoxides of Cr(II) were prepared by alcoholysis of Cr[N(SiMe3)2]2LL′, where L, L′ = ether, THF, or Py. They were characterized by elemental analyses, reflectance spectroscoppy, solubility, and chemical behavior. Solubility of the alkoxides is influenced most by drying conditions. Thoroughly dried aliphatic products are quite insoluble and exhibit coordinations polymer characteristics. Sterically hindered alkoxides are less associated, more soluble in general, and tend to form crystalline adducts with donor ligands. Primary alcohols (except MeOH) gave yellow/brown, secondary alcohols purple/violet and tertiary alcohols (as well as many phenols) blue derivatives. Some chemical reactions of selected alkoxides are discussed. 相似文献
12.
Ram Chand Paul Surinder Kumar Gupta Veena Goyal Sham Kumar Vasisht 《Monatshefte für Chemie / Chemical Monthly》1977,108(5):1019-1025
Oxozirconium(IV) alkoxides of the type ZrO(OR)2·ROH and ZrOCl(OR)·2 ROH, where R is methyl, ethyl, and isopropyl, and ZrO(OCMe
3)2·0.5Me
3COH and ZrOCl(OCMe
3)·1.5Me
3COH have been prepared by the reaction of dichloroxozirconium(IV)-2-acetic acid with corresponding alcohols in the presence of appropriate amounts of piperidine. The alkoxides have been isolated and characterised through infrared, thermal and conductance studies. 相似文献
13.
Jang-Woo Kim Frank S. Davis Liang-Fu Huang Salma M. Abdelaal Subhash P. Upadhyaya Jae Jeong Lee Ludwig Bauer 《Journal of heterocyclic chemistry》1996,33(1):65-74
Aryl 2-[(2-imidazolyl)ethyl or 3-(2-imidazolyl)propyl]ketones were ketalized by glycerol or 3-mercapto-1,2-propanediol in boiling benzene in the presence of 4-toluenesulfonic acid to provide the title compounds. The aryl substituents are 4-chloro-, 4-bromo-, 4-fluoro-, or 2,4-dichlorophenyl. While aryl (2-imidazolyl)methyl ketones condensed with glycerol to form cis- and trans-{2-aryl-2-[(2-imidazolyl)methyl]-4-(hydroxymethyl)}-1,3-dioxolanes, related condensations with 3-mercapto-1,2-propanediol, under similar, or even more stringent reaction conditions, produced no 1,3-oxathiolane analogs, with the starting ketones being recovered. Separation and structure determination of these racemic cis and trans isomeric products are described. The structure of these stereoisomers was established by means of 1H and 13C nmr correlation and nOe experiments. Selective methylation of the N-unsubstituted 2-imidazolyl alcohols with one equivalent sodium hydride and methyl iodide provided the corresponding N-methyl alcohols in excellent yields. With excess benzoyl chloride, N-unsubstituted 2-imidazolyl alcohols were initially converted to O, N-dibenzoates from which the N-benzoyl group was easily cleaved by ammonium hydroxide in ethanol to provide benzoate esters. 相似文献
14.
Clara Pampillón James Claffey Megan Hogan Katja Strohfeldt Matthias Tacke 《Transition Metal Chemistry》2007,32(4):434-441
Abstract From the carbolithiation of 6-N,N-dimethylamino fulvene (3a) and different ortho-lithiated indole derivatives (5-methoxy-N-methylindole, N-methylindole and N,N-dimethylaminomethylindole), the corresponding lithium cyclopentadienide intermediate (4a–c) was formed. These three lithiated intermediates underwent a transmetallation reaction with TiCl4 resulting in dimethylamino-functionalised titanocenes (5a–c). When these titanocenes were tested against LLC-PK cells, the IC50 values obtained were of 37 and 71 μM for titanocenes 5a and 5b respectively. The most cytotoxic titanocene in this paper, 5c showed an IC50 value of 8.4 μM is found to be almost as cytotoxic as cis-platin, which showed an IC50 value of 3.3 μM, when tested on the LLC-PK cell line, and titanocene 5c is approximately 250 times better than titanocene dichloride itself.
Graphical Abstract Bis-(N,N-dimethylamino-2-(N-methylindolyl)methylcyclopentadienyl) titanium (IV) dichloride was synthesised starting from 2-(N-methylindolyl) lithium and 6-N,N-dimethylamino fulvene. Herein, we present the synthesis and DFT structure of the titanocene and two further derivatives followed
by MTT-based cytotoxicity tests on LLC-PK cells.
相似文献
15.
Shuji Kondo Shinya Kawasoe Mari Ohira Tadashi Atarashi Kazahisa Ikeda Hideo Kunisada Yasuo Yuki 《Macromolecular rapid communications》1995,16(4):291-295
A polymer containing dichlorotriazine moiety was prepared readily by the reaction of poly(2,4-diamino-6-vinyl-1,3,5-triazine) with tert-butyl hypochlorite. This polymer oxidizes various primary and secondary alcohols to the corresponding carbonyl compounds under mild conditions, while the reaction of the monomeric analogue N,N′-dichloroacetoguanamine with alcohols does not proceed. The polymer reagent can be handled easily and recycled for further use. 相似文献
16.
An efficient and mild methodology for the oxidation of primary and secondary alcohols to the corresponding carbonyl functions is described with N,N,N′,N′‐tetrabromobenzene‐1,3‐disulfonamide and poly(N‐bromobenzene‐1,3‐disulfonamide) using microwave irradiation under solvent‐free conditions. Aliphatic, benzylic and allylic alcohols are rapidly oxidized without over‐oxidation to carboxylic acids. Secondary carbinols are slowly oxidized so that the reaction is highly chemoselective. 相似文献
17.
Jan Bergman 《Journal of heterocyclic chemistry》1985,22(2):341-343
Indole and N-methylindole react with oxa stabilized carbocations generated in situ from orthoformates to yield tris(3-indolyl)methane. The unsymmetrical isomers, e.g. 2-(N-methyl-3-indolyl)di(N-methyl-3-indolyl)-methane ( 4 ), were not formed as established by an independent synthesis. N,N-Dimethylacetamide dimethyl-acetal reacted with 2-alkyl substituted indoles to produce 1,1-bis(3-indolyl)ethanes ( 3 ). 相似文献
18.
The reaction of trans,trans-[WH(CO)2(NO)(PMe3)2] ( 1 ) with (pyridin-2-yl)-substituted aldehydes and ketones, (pyridin-2-yl)C(O)R where R = H, Me, Ph, pyridin-2-yl, and with 6-methylpyridine-2-carbaldehyde was studied. In all cases, facile insertion of the C?O bond into the W? H bond was observed, with rapid subsequent extrusionof a coordinated CO ligand affording O,N-bidentate coordinated tungsten alkoxides. Only in case of pyridine-2-carbaldehyde and di(pyridin-2-yl) ketone, the initial n1 O-bonded insertion product could be observed as unstable intemediates by low-temperature NMR. 相似文献
19.
D. N. Bazhin T. I. Gorbunova A. Ya. Zapevalov V. I. Saloutin 《Russian Chemical Bulletin》2008,57(11):2324-2327
On treatment with sodium alkoxides in the corresponding alcohols, [2-iodo-3-(perfluoroalkyl)propyl]glycidyl ethers are converted
into 3-alkoxy-1-[3-(perfluoroalkyl)prop-2-enyloxy]-propan-2-ols in 56–78% yields, while its reaction with 2,2,2-trifluoroethanol
and phenol under phase transfer conditions (NaOH, CH2Cl2-H2O, Bu4N+I−, 35–40 °C) gives 3-alkoxy1-[2-iodo-3-(perfluoroalkyl)propoxy]propan-2-ols (yields 45–72%). 相似文献
20.
The reaction of dimethyl(methylthio)sulfonium trifluoromethanesulfonate (DMTST) with o-allylphenol gave 2-methylthiomethyl-2,3-dihydrobenzofuran in 97% yield. The reaction of DMTST with N-tosyl-o-isopropenylanilide followed by the addition of aq sodium carbonate afforded N-tosyl-3-methylindole in 88% yield, whereas N-tosyl-o-vinylanilide afforded N-tosylindoline in 85% yield. 相似文献