Search results for "Acetophenone"
showing 9 items of 49 documents
Über umsetzungen an poly-p-lithiumstyrol. 4. Mitt. Darstellung carbonylgruppenhaltiger derivate des polystyrols
1961
In Fortsetzung fruherer Arbeiten wird die Reaktivitat von Poly-p-lithiumstyrol gegenuber solchen Agenzien gepruft, die zur Bildung von carbonylgruppenhaltigen Verbindungen fuhren. Wahrend bei der Umsetzung mit Orthoameisensaureester nur vernetzte Polymere entstechen, last sich mit Dimethylformamid ein losliches Derivat des Polystyrols herstellen das p-standige Formylgruppen tragt. Die Reaktion mit Nitrilen liefert polymere Ketone; mit Acetophenon entsteht Poly-p-vinylacetophenon, das mit dem aus dem Monomeren durch Polymerisation erhaltenen Produkt verglichen wird. Mit Benzonitril erhalt man Poly-p-vinylbenzophenon. Die polymeren Ketone konnen in die Oxime ubergefuhrt werden, deren Sticksto…
Studien zum Vorgang der Wasserstoffübertragung, 47.Elektroreduktion von 1,4-Benzoldicarbonitril, 1,4-Diacetylbenzol und Terephthalaldehyd
1978
Die Elektroreduktion von 1,4-Benzoldicarbonitril in Gegenwart von Essigsaure fuhrt bei einem Stromdurchgang von 4.5 Faraday-aquivalenten/mol in 80proz. Ausbeute zu 4-Amino-methylbenzonitril (1). Bei Anwendung von 6 Faraday-aquivalenten/mol konnen geringe Mengen an 4-Methylbenzonitril (2) nachgewiesen werden. Bei der praparativen Elektroreduktion von 1,4-Diacetylbenzol in Gegenwart unterschiedlicher Mengen an Essigsaure entstehen 4-(1-Hydroxyethyl)acetophenon (3), 1,1′-(1,4-Phenylen)diethanol (4) sowie polymere Pinakole 5 in den in Tabelle 1 angegebenen Mengen. Terephthalaldehyd wird in Gegenwart von Essigsaure zu 4-Hydroxymethylbenzaldehyd (6), Terephthalalkohol (7) und einem polymeren Pina…
Darstellung von phenolischen verbindungen und phenol/formaldehyd-polykondensaten mit ketoxim-, aldoxim- oder 1-methyl-4-hydroxyiminomethylpyridinium-…
1979
Thirteen low molecular weight oximes were prepared: one derivative of acetophenone (1), two derivatives of benzophenone (2 and 3), two derivatives of salicylaldehyde containing two phenolic nuclei (4c and 5c), and eight compounds in which a phenol unit is substituted by a 4-hydroxyiminomethylpyridiniummethyl group (8a–f, 10c, and 11c). Besides these compounds polymeric phenol formaldehyde condensates were synthesized which contain units deriving from benzophenoneoxime (15b) or from salicylaldehyde (22b) and condensates containing 4-hydroxyiminomethylpyridiniummethyl groups (23c). A series of low molecular weight and water soluble compounds (8a–f) were proved as antidotes on mice which were …
Studien zum Vorgang der Wasserstoffübertragung, 41. Elektroreduktion von Acetophenon unter Mitwirkung optisch aktiver Leitsalze
1977
Die Anderung des Carbinol/Pinakol-Verhaltnisses2) (C/P) und der optischen Induktion bei der Elektroreduktion von Acetophenon mit (1 R, 2S)-N-(3-Cyanpropyl)-N-methylephedriniumbromid (1) und (1 R, 2 S)-N,N-Dimethylephedriniumbromid (2) als Leitsalze wird untersucht in Abhangigkeit: a) vom Potential (Tabelle 1), b) von der Stromdichte (Tabelle 2), c) von Pulsbedingungen (Tabelle 3), d) vom pH (Tabelle 4), e) von der Anwesenheit anderer Kationen (Tabelle 5), f) vom Losungsmittel (Tabelle 6), g) von der Temperatur (Tabelle 7) und h) von der Art des Elektrodenmaterials (Tabelle 8). — Es werden tensammetrische und cyclovoltammetrische Messungen durchgefuhrt. Die in trockenem Dimethylformamid erha…
Ringoffene Serotonin-Analoga, 2. Mitt.1) Synthese von 3-(2-Aminophenyl)-propanamin- und 1-(N-Piperidino)-3-(2-aminophenyl)-3-oxo-propan-Derivaten
1983
Die Darstellung der Titelverbindungen gelingt via Mannich-Reaktion beim Einsatz geeignet substituierter Acetophenone. Die Gewinnung von 2 und seiner Derivate erfordert zusatzlich die nachfolgende durchgreifende Hydrierung der Carbonylgruppe der entsprechenden Mannichbasen. Ring-Opened Analogues of Serotonine, II: Synthesis of 3-(2-Aminophenyl)propanamine and 1-(Piperidin-1-yl)-3-(2-aminophenyl)propan-3-one and Their Derivatives The synthesis of the title compounds was achieved by Mannich reaction of suitably substituted acetophenones. The preparation of 3-(2-aminophenyl)propanamine and its derivatives requires complete hydrogenation of the carbonyl group of the Mannich bases.
Convenient Synthesis of 3-Cinnamoyl-2-styrylchromones: Reinvestigation of the Baker-Venkataraman Rearrangement
2010
An efficient and straightforward, one-pot sequence gives access to highly functionalized 3-cinnamoyl-2-styrylchromones in excellent yields. The low solubility of the target molecules allows convenient isolation. The formation of an α,α-dicinnamoylated acetophenone, as a consequence of a two-fold Baker-Venkataraman sequence, has to be anticipated.
An unexpected ring carboxylation in the electrocarboxylation of aromatic ketones
2006
The electrocarboxylation of various aromatic ketones, carried out in N-methyl-2-pyrrolidone (NMP) in a diaphragmless cell equipped with a carbon cathode and an aluminium sacrificial anode, yielded, among the products, the target hydroxy acids, the corresponding alcohols and pinacols and, quite surprisingly, detectable amounts of substituted benzoic acids and cycloexene carboxylic acids. These compounds arise from a never reported before electrocarboxylation on the aromatic ring, respectively, for substitution of an aromatic hydrogen and from an addition reaction. For example, the electrocarboxylation of acetophenone gave rise to the substituted benzoic acids in ortho, para and meta position…
Volatile compounds of flowers and leale of Sideritis italica (Miller) Greuter et Burdet used as mountain tea
2010
Sideritis italica (Miller) Greuter et Burdet (Lamiaceae), widely used in ethnopharmacological medicine, occurs in Southern Italy and Sicily. The phytochemical composition of the essential oils of S. italica flowers and leaves, harvested in Piano Battaglia (Sicily), was analysed by GC and GC-MS. Of the 51 compounds, 43 in the oil from flowers and 29 in the oil from leaves were identified. Kaur-15-ene (20.0%) was recognised as the main constituent of the oil from flowers, together with -cubebene (12.1%), -pinene (8.5%), (Z)-nuciferol (6.5%), tricyclene (4.5%) and -bisabolol (4.0%). In the oil from leaves, p-methoxyacetophenone (26.0%) prevailed, as did hexadecanoic acid (21.3%), followed by n…
Synthesis of 6,12-Disubstituted Methanodibenzo[b,f][1,5]dioxocins : Pyrrolidine Catalyzed Self-Condensation of 2′-Hydroxyacetophenones
2019
The preparation of unprecedented 6,12-disubstituted methanodibenzo[b,f][1,5]dioxocins from pyrrolidine catalyzed self-condensation of 2′-hydroxyacetophenones is herein described. This method provides easy access to this highly bridged complex core, resulting in construction of two C–O and two C–C bonds, a methylene bridge and two quaternary centers in a single step. The intricate methanodibenzo[b,f][1,5]dioxocin compounds were obtained in up to moderate yields after optimization of the reaction conditions concerning solvent, reaction times and the use of additives. Several halide substituted methanodibenzo[b,f][1,5]dioxocins could be prepared from correspondent 2′-hydroxyacetophenones.