Showing papers on "Methyl vinyl ketone published in 1985"
TL;DR: In this article, conjugated dienoates, dienones and dienals are obtained with high stereospecificity (⩾95%) and in high yields from the corresponding (E,E) and (Z) vinylic halides, and substrates (methyl acrylate, methyl vinyl ketone or acrolein).
285 citations
TL;DR: In this paper, a low total pressure (10 torr) flowing gas system and a high total pressure CH/sub 3/ON-O-NO photolysis system were used to study the reaction of OH with isoprene.
Abstract: A low total pressure (10 torr) flowing gas system and a high total pressure (760 torr) CH/sub 3/ON-O-NO photolysis system are used to study the reaction of OH with isoprene. Both systems give methyl vinyl ketone, methacrolein, and 3-methylfuran as the major products; 1,2-addition is favored over 1,4-addition by a factor of 7. From the proposed mechanism and reaction pathways, it is concluded that more than 2 mol of NO will be oxidized to NO/sub 2/ for each mole of isoprene oxidized by OH. Direct reaction of isoprene with NO/sub 2/ was also measured.
86 citations
TL;DR: The higher activity of the C-6 methyl and methoxyl analogues (R)-15 and (R-22 relative to hydrogen-substituted ( R)-19 indicates that C- 6 alkyl substitution enhances analgesic potency.
Abstract: 6-Deoxythebaine (3) has been prepared as a precursor to C-6 alkyl substituted orvinols 15 and 17. The C-6 methyl group was introduced by addition of methyllithium to codeinone. Transformation of 6-methylcodeine to its 6-methyl ether and 1,4-elimination of methanol with potassium tert-butoxide in Me2SO then gave 6-deoxythebaine (3) in 49% overall yield. Diels-Alder addition of methyl vinyl ketone to this diene yielded four ketones: three regio- and stereoisomeric 6,14-endo-ethenomorphinans and one exo adduct. The major ketone isomer provided the set of C-19 diastereomeric orvinols 15 in which the pendant carbon has the 7 alpha configuration. Regioisomeric ketone 8, in which the acetyl group is at C-8, was formed in 3% yield and was similarly converted to the corresponding orvinols 17. Orvinol (R)-15 (R at C-19) is an analgesic of very high potency, 2200 times that of morphine; regioisomeric orvinols 17, in which the pendant tertiary alcohols are on C-8, are much less potent. The higher activity of the C-6 methyl and methoxyl analogues (R)-15 and (R)-22 relative to hydrogen-substituted (R)-19 indicates that C-6 alkyl substitution enhances analgesic potency.
31 citations
TL;DR: In this paper, a method for 1,5-dicarbonyl compounds from enol ethers, methyl vinyl ketone and boron triflouride etherate was described.
22 citations
TL;DR: In this article, the reaction of N′,N′-substituted N2-thiobenzoylformamidines with methyl vinyl ketone or acrylaldehyde is described.
Abstract: 5-Acyl-2-phenyl-4-substituted 6H-1,3-thiazines are prepared by the reaction of N′,N′-substituted N2-thiobenzoylformamidines with methyl vinyl ketone or acrylaldehyde. Rearrangement catalysed by base and subsequent condensation with the acrylic reagent gives substituted pyrrolyl sulphides or substituted 2,6-dihydrothiopyrano[2,3-c]pyrrole.
9 citations
TL;DR: In this paper, two regioisomeric α-naphthols obtained by aromatization of the methyl vinyl ketone adducts of an unsymmetrical isobenzofuran were differentiated from each other by the observation of significant upfield shifts of the peri proton resonances in the 1H nmr spectra of their acetates.
Abstract: Two regioisomeric α-naphthols 14 and 15 obtained by aromatization of the methyl vinyl ketone adducts of an unsymmetrical isobenzofuran 9 are differentiated from each other by the observation of significant upfield shifts of the peri proton resonances in the 1H nmr spectra of their acetates 16 and 17. Such upfield shifts of 0.3–0.6 ppm appear to be a general phenomenon and are probably due to the anisotropic effect of the acetate carbonyl group.
9 citations
TL;DR: The Michael reaction of 1,2-cyclohexanediones with methyl vinyl ketone is highly dependent upon the structure of dione or the catalyst, base or ZnCl2.
Abstract: The Michael reaction of 1,2-cyclohexanediones with methyl vinyl ketone is highly dependent upon the structure of dione or the catalyst, base or ZnCl2, affording 3-(3-oxobutyl)-2-hydroxy-2-cyclohexen-1-one or 1-hydroxy-7-acetylbicyclo[3.2.1]octan-8-one as major products. 1,2-Cyclopentanediones react with methyl vinyl ketone somewhat differently.
7 citations
TL;DR: The syntheses of 1,2-di-(O-hexadecyl)-rac-glycero-3-phosphocholines containing a methyl group at either C1 or C3 of the glycerol moiety are described and may be useful for investigating the effect of steric bulk at C1 and C1 of the GlycerolMoiety on the interactions with membrane components.
6 citations
TL;DR: One-pot annelation of 6,8-dimethoxytetralone by first forming a β-keto sulfoxide, then addition of methyl vinyl ketone, gave, unexp...
Abstract: Two synthetic approaches to cannithrene 1 (1) have been explored. One-pot annelation of 6,8-dimethoxytetralone by first forming a β-keto sulfoxide, then addition of methyl vinyl ketone, gave, unexp...
5 citations
TL;DR: In this paper, the olefins acrylonitrile, acrolein, crotonaldehyde and methyl vinyl ketone were added to vanadocene to form the corresponding metallacycle.
5 citations
TL;DR: In this article, the copolymer (4VK) of 4-vinylpyridine (4VP) and methyl vinyl ketone (MVK) was nearly quantitatively converted into an oxime, which could be complexed with various metal salts.
Abstract: The copolymer (4VK) of 4-vinylpyridine (4VP) and methyl vinyl ketone (MVK) was nearly quantitatively converted into an oxime (4VKX) which could be complexed with various metal salts. 4VKX was compared with 4VK in their membrane performance. When crosslinked with divinyl sulfone (DVS), the 4VKX membrane showed a higher strength than cellulose acetate (CA) membrane and a higher performance than 4VK membrane crosslinked with dihydrazine derivatives. The most adequate DVS content and copolymer composition were found to be 25 mol % based on MVK oxime and 1:1, respectively. A metal salt taken up by the membrane in a much larger amount tended to be highly rejected. The crosslinking quaternization of 4VKX with diisobutane (DIB) very effectively improved water permeability, as did 4VK, and gave a membrane performance superior to that of 4VK. The most appropriate charge ratio of DIB was 15–20 mol % based on 4VP. Some transport characteristics and compaction in a long-term operation were investigated and discussed.
TL;DR: The direction of the addition is mainly influenced by steric factors as mentioned in this paper, i.e., the direction of addition is mostly influenced by the steric factor of the quinone 5a and 18-21.
TL;DR: Methyl vinyl ketone cyanohydrin phosphate was found to react with aromatic compounds in the presence of borontrifluoride etherate to give 4-arylangelonitriles.
Abstract: Methyl vinyl ketone cyanohydrin phosphate was found to react with aromatic compounds in the presence of borontrifluoride etherate to give 4-arylangelonitriles.
Patent•
04 Jun 1985
TL;DR: In this article, a simple process in high selectivity in high yield, by reacting a ketone with methanol as the raw materials by the use of a catalyst consisting of Fe-Mg-O system was proposed.
Abstract: PURPOSE:To obtain the titled compound useful as perfume, drugs, etc from enexpensive raw materials by a simple process in high selectivity in high yield, by reacting a ketone with methanol as the raw materials by the use of a catalyst consisting of Fe-Mg-O system CONSTITUTION:A ketone shown by the formula I (R is 1-4C alkyl, or 6-10C aryl) such as acetone and methanol are preferably vaporized, and reacted in the presence of a catalyst shown by the formula II(a, b, and c are 05-20, 48-60, and 32-395wt%, respectively, with the proviso that a+b+c=100) comprising Fe, Mg and O at 250-450 degC for 05-8sec, preferably about atmospheric pressure to give the desired compound shown by the formula III such as methyl vinyl ketone, etc A ketone having one more carbon is obtained from a starting raw material shown by the formula IV The catalyst, for example, is prepared by impregnating MgO with an aqueous solution of tetravalent Fe nitrate, drying it at 20-60 degC for 12-14hr, molding it, calcining it at 300-700 degC for 1-10hr
TL;DR: A series of optically active podands incorporating ether and chiral sulfoxide functionality have been synthesized in this paper, where the podands formed relatively strong complexes with protonated amines.
Abstract: A series of optically active podands incorporating ether and chiral sulfoxide functionality have been synthesized. The podands formed relatively strong complexes with protonated amines. Where racemic guests were used, the diastereoisomeric complexes were identified in solution by 1H n.m.r. spectroscopy but the energies of formation of these complexes were too similar to afford optical resolution of guests. The podands influenced the stereochemistry of t-butoxide-catalysed additions of methyl 1-oxoindane-2-carboxylate to methyl vinyl ketone, but stereoselectivities observed were low.
TL;DR: The direction of the addition is mainly influenced by steric factors as discussed by the authors, i.e., the direction of addition is mostly influenced by the steric factor of the quinone 5a and 18-21.
Abstract: Except from 1,4,9,10-anthracenetetrols, 9,10-anthrahydroquinones (derived from the quinones 5a and 18– 21) react with unhindered Michael acceptors such as acrylate, acrylonitrile, acrylaldehyde, and methyl vinyl ketone with addition at C-9 or C-10 to yield anthrones. The direction of the addition is mainly influenced by steric factors.
Reaktion von Anthrahydrochinonen mit α,β-ungesattigten Carbonylverbindungen
Mit Ausnahme der 1,4,9,10-Anthracentetrole reagieren 9,10-Anthrahydrochinone (abgeleitet von den Chinonen 5a und 18–21) mit ungehinderten Michael Akzeptoren wie Acrylester, Acrylonitril, Acrylaldehyd und Methylvinylketon unter Addition an C-9 oder C-10 zu Anthronen. Die Additionsrichtung wird vorwiegend durch sterische Faktoren gelenkt.
TL;DR: The Michael reaction of 1,2-cyclohexanediones with methyl vinyl ketone is highly dependent upon the structure of dione or the catalyst, base or ZnCl2 as mentioned in this paper.
Abstract: The Michael reaction of 1,2-cyclohexanediones with methyl vinyl ketone is highly dependent upon the structure of dione or the catalyst, base or ZnCl2, affording 3-(3-oxobutyl)-2-hydroxy-2-cyclohexen-1-one or 1-hydroxy-7-acetylbicyclo[3.2.1]octan-8-one as major products. 1,2-Cyclopentanediones react with methyl vinyl ketone somewhat differently.
TL;DR: In this article, a five-stage synthesis of exo- and endo-brevicomins was carried out from acrolein and methyl vinyl ketone, with an oxy-Cope rearrangement of 4-ethyl-3-methyl-1,5-hexadien-3ol as the key stage.
Abstract: A five-stage synthesis of exo- and endo-brevicomins was carried out from acrolein and methyl vinyl ketone, with an oxy-Cope rearrangement of 4-ethyl-3-methyl-1,5-hexadien-3-ol as the key stage.