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1.
I. Petneházy Zs. M. Jászay Gy. Keglevich L. Toke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract Reaction of trialkyl phosphites 1 with α,β-unsaturated oxo-compounds 2 gives oxaphospholenes 3 or/and two types of Arbuzov products, γ-keto-phosphonates 4 and alkyl-enol-ethers 5. 相似文献
2.
Vladimir I. Galkin Gulchira M. Saakyan Irina V. Galkina Rafael A. Cherkasov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Elaboration of effective methods of selective phosphorylation of α,β-unsaturated carbonyl compounds containing simultaneously C[dbnd]C and C[dbnd]O bonds, which may compete with each other or react consistently one after another, is one of the most complex problems in the modern organophosphorus synthesis. On the basis of our previous systematic investigations of kinetics and mechanism of the Pudovik and Abramov reactions in the series of α,β-unsaturated carbonyl compounds we have suggested three possible ways to solve this problem: a) soft reaction conditions, regulated by solvent, catalyst and temperature; b) interface catalysis; c) metallocomlex catalysis (reaction in the coordination sphere of transition metal). 相似文献
3.
Ying CHANG Chun CAI 《中国化学快报》2005,16(10):1313-1316
In the presence of copper (I) halide as catalyst, a variety of carbonyl compounds could be trifluoromethylated with sodium trifluoroacetate to give the corresponding alcohols in moderate to high yields. 相似文献
4.
The hydrogen-Lindlar catalyst system is effective for the highly regioselective reduction of α,β-unsaturated carbonyl compounds to the corresponding α,β-saturated compounds. 相似文献
5.
Abstract The reaction of N-phenyliminoketenylidenetriphenylphosphorane [a] (1), with 2-benzylidene-1, 3-indandione (2), 1,2-diphenyl-3,4-pyrazolidenedione (3)and/or 5-benzylidene barbituric acid (4) has been investigated. When ylide 1 was allowed to react with compounds 2, 3 or 4 in THF at ambient temp. the corresponding new pyrano-phosphoranylidenes 5, 6 or 7 were obtained. The elemental microanalyses, IR, 1H NMR, 31P NMR and MS data agree with the structure of the cyclic iminophosphoranes by [4+2]-cycloaddition and exclude 4-membered ring structure by [2+2]-cycloaddition. When the Wittig reaction was carried on the pyrano-phosphoranes 5, 6 or 7 using p-nitrobenzaldehyde, the exocyclic olefins together with triphenylphosphine oxide were isolated. 相似文献
6.
Attheendof1930s,ThesynthesisofMn(C6H6)21firstreportedbyH.Gilmanattractedmuchattention.Subsequently,manyneworgano-manganesecompoundshavebeensythesized.Inthe1950s,itwasfoundthatCPMn(CO)3andsomeofitSderivativesaughtactastheantiknockofgasolinetosubstitutetetra-ethylleadwhichisveryharmfultoourenvironment.Thisfindinghasattractedpeople'sinterestinthestudyofthisfield.Inthiswork,weobtainedtwonewcompoundsthroughthesubstitutionreactionbetweenmixeddonorphosphineligand2,6-di(hi-phenylphosphine)pyridme… 相似文献
7.
Sal'keeva L. K. Nurmaganbetova M. T. Kurmanaliev O. Sh. Gazizov T. Kh. 《Russian Journal of General Chemistry》2002,72(11):1760-1763
Reactions of ethyl and tert-butyl phosphorodiamidites with chloroacetone, bromoacetone, and -chloroethyl acetate were studied. The reaction pathway is determined by the structure of the intermediate quasiphosphonium compound responsible for the formation of the Arbuzov product as well as for the occurrence of the amonalous reaction yielding vinyl phosphate. 相似文献
8.
Ovakimyan M. Zh. Gasparyan G. Ts. Poghosyan A. S. Bichakhchyan A. S. Derdzyan L. V. 《Russian Journal of Organic Chemistry》2020,56(1):90-94
Russian Journal of Organic Chemistry - Procedures were developed for the synthesis of diphenyl(prop-1-en-1-yl)phosphine oxide and cyclohex-1-en-1-yl(diphenyl)phosphine oxide by alkaline hydrolysis... 相似文献
9.
《有机化学》1993,(2)
The duality in electronic effect of sydnone ring and the effect of delocalization of 4-substitutedgroup to sydnone ring are investigated by the nitration of 3-benzyl-4-phenylsydnone and 4-formyl-3-arylsydnones. Sydnones are typical mesoionic compounds and their chemical, physical and biological properties 相似文献
10.
P-Selenium and β-tellurium carbonyl compounds have been prepared in good yield by reaction of diaryldiselenides or diarylditelluride with α,β-unsaturated carbonyl compounds induced by TiC14 / Sm /THF system under mild reaction conditions. 相似文献
11.
I. S. Levina L. E. Kulikova V. V. Kachala L. L. Khemchyan 《Russian Chemical Bulletin》2013,62(9):2037-2040
On treatment with methylmagnesium iodide, 3β-acetoxy-5β,6β-epoxy-16α,17α-cyclo-hexapregnan-20-one undergoes 3-O-deacetylation along with the opening of the 5β,6β-epoxide ring to form 5α-methyl-6β-hydroxy steroid and the 6α-methyl-6β-hydroxy isomer, the 20-keto group remaining intact. 相似文献
12.
Zhengyu Li Yizhi Zhang Dr. Yunxiao Zhang Xingyi He Prof. Dr. Xiao Shen 《Angewandte Chemie (International ed. in English)》2023,62(20):e202303218
Monofluoroalkenes are nonhydrolyzable mimetics of amides. Previous work focused on the synthesis of non-cyclic monofluoroalkenes. However, diastereoselective synthesis of monofluorocyclohexenes from non-cyclic substrates is challenging. Herein, we report the first photocatalyzed cascade cyclization reactions of readily available α,β-unsaturated carbonyl compounds and gem-difluoroalkenes for the synthesis of highly functionalized monofluorocyclohexenes. The reaction shows broad substrate scope with high diastereoselectivity (>30 examples, up to 86 % yield, >20 : 1 dr). The post-reaction transformations of the products demonstrate the synthetic potential of this methodology. 相似文献
13.
L. V. Serebrennikov A. V. Golovkin D. I. Davlyatshin V. F. Shevel’kov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(4):558-564
The paper presents the results obtained for the malonic aldehyde—hydrogen peroxide and β-oxobutanal—hydrogen peroxide systems. The systems were studied by IR spectroscopy in xenon matrices. The potential energy surfaces and vibrational spectra of the molecules that could occur in these systems were calculated quantum-chemically. As distinct from similar systems with monoaldehydes and α-dioxo compounds, the first stage of the reactions that occurred in the systems under consideration involved the decomposition of hydrogen peroxide with the formation of atomic oxygen, whose secondary reactions determined the set of reaction products. 相似文献
14.
It has been established that on the interaction of the 5,6-epoxysteroids (1a–c) with trifluoroacetic acid in chloroform the 6-trifluoroacetates of the 5,6-diols (2a–c) are formed in high yield. The alkaline hydrolysis of the trifluoroacetates (2a–c) leads to the corresponding diols (3a–c).Institute of Bioorganic Chemistry, Belarus' National Academy of Sciences, 220141, Belarus', Minsk, ul. Akad. Kuprevicha, 5/2. Translated from Khimiya prirodnykh Soedinenii, No. 2, pp. 201–204, March–April, 1999. 相似文献
15.
Makarenko S. V. Trukhin E. V. Berestovitskaya V. M. 《Russian Journal of General Chemistry》2003,73(4):603-606
The reactions of ,-dibromo--nitrostyrenes with acetylacetone and ethyl acetoacetate were studied. The structures of the products were determined by 1H NMR, IR, and UV spectroscopy. The products derived from acetylacetone were converted into copper chelates. 相似文献
16.
β-Sulfinyl α,β-unsaturated ketones (2a-f) reacted in a regioselective manner with dienes such as butadiene (3a) and 1,3-pentadiene (3b) to give 1,4-cyclohexadiene derivatives (4-8) with the concomitant elimination of sulfenic acid, while the ketones (2a-c) reacted with cyclopentadiene (3c) to yield the norbornenes (9). 相似文献
17.
In the course of current work on the conformational analysis of cis-hydrindanones1, we required 5α, 13α, 14α and 5α, 13β, 14β-androstan-16-one 5 and 10 the C and D rings of which provide rigid models of the two conformations of cis-hydrindan-2-one. 相似文献
18.
19.
Edith Gößnitzer Winfried Wendelin Karl Schermanz Karin Frieberger 《Monatshefte für Chemie / Chemical Monthly》2001,132(9):1081-1093
Summary. The reaction of 2-benzylidenecyclohexanone and 1-(4-methoxyphenyl)-2-methyl-1-penten-3-one with guanidine did not yield the
expected 4-phenylhexahydro-2-quinazolinamine and 4-(p-methoxyphenyl)-dihydro-2-pyrimidinamine, respectively, but nitrogen-free products which turned out as [3+3]- and [4+2]-cycloadducts
of two molecules of the applied vinylogous ketone each. According to elemental analyses, mass spectra, and, in particular,
NMR analyses (1H and 13CNMR, HH-COSY, gs-HSQC, gs-HMBC, 1D TOCSY, NOESY, and 1D NOE difference spectra), the prepared dimers were identified as racemic (5E)-5-benzylidene-9β-phenyl-trans-4a-1,2,3,4,4a,5,6,7,8,9a-decahydroxanthen-4aα-ol and 3β,5β-bis-(4-methoxyphenyl)-2α,4β,6α-trimethyl-4α- propionylcyclohexanone, respectively. Structure and stereochemistry of the dimers
are elucidated, and mechanisms for their formation are proposed.
Received April 11, 2001. Accepted (revised) May 18, 2001 相似文献
20.
《有机化学》1993,(3)
It was found for the first time that carbon dioxide under pressure could carboxylate lithium tri-alkylalkynylborate. In the reaction, carbon dioxide attackedd the β-carbon of the alkynyl group and analkyl group migrated from boron to the α-carbon of the alkynyl group, followed by protonation, giv- 相似文献