| | 1 | Author
| Georg Ziegler3, Erwin Haug3, Wolfgang Freyb, Willi Kantlehner3 | Requires cookie* | | | Title
| Orthoamide, LVII [1]. Lassen sich aromatische Aldehyde nach Fries aus Arylformiaten hersteilen? Orthoamides, LVII [1]. Can Aromatic Aldehydes be Prepared from Aryl Formates via the Fries Rearrangement?  | | | | Abstract
| The aromatic hydroxyaldehydes 3a-3g, 5a-5f, 8 , 10 can be prepared by the action of BC13, BBr3 or trifluoromethanesulfonic acid, on the aryl formates la-lf, 4a-e, 7, 9 via Fries rear rangement. BBr3 is more effective than BC13. The activating ability of BBr3 can be improved by addition of FeCl3. Rearrangements which are induced by trifluoromethanesulfonic acid can give rise to the formations of regioisomers, which might be different from the products formed when the reaction is performed with Lewis acids. The yields of the aldehydes are lowered by subsequent condensation reactions. This view was confirmed by the isolation of a con densation product, which was characterized as a dibenzo[a,y']xanthene derivative 6 by crystal structure analysis. For the Fries rearrangement of formyl groups a new mechanism is proposed. 2-Hydroxy-1-naphthaldehyde 5c can be obtained in good yield from formic acid, BBr3, and 2 -naphthol. | | | |
Reference
| Z. Naturforsch. 56b, 1178—1187 (2001); eingegangen am 13. Juli 2001 | | | |
Published
| 2001 | | | |
Keywords
| Aromatic Hydroxyaldehydes, Fries Rearrangement, Formylation | | | |
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| default:Reihe_B/56/ZNB-2001-56b-1178.pdf | | | | Identifier
| ZNB-2001-56b-1178 | | | | Volume
| 56 | |
| 2 | Author
| V. Salas-R, G. Eyesa, Soto-G, C. A. Arridob, Guilera0 | Requires cookie* | | | Title
| Synthesis and Characterization of Bis(3-chloro-4-dodecyloxyphenyl) Malondialdehyde Complexes of Cu(II) and Ni(II) | | | | Abstract
| Bis (3-chloro-4-dodecyloxyphenyl) malondialdehyde copper(II), as well as its nickel(II) homologue have been synthesised. The copper(II) complex shows a narrow (15 °C) nematic phase below its clearing temperature. The nickel(II) complex is polymeric in nature. | | | |
Reference
| Z. Naturforsch. 51b, 1679—1682 (1996); received July 8 1996 | | | |
Published
| 1996 | | | |
Keywords
| Metallomesogens, Liquid Crystals, Copper Complexes, Dialdehydes, Formylation | | | |
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| default:Reihe_B/51/ZNB-1996-51b-1679.pdf | | | | Identifier
| ZNB-1996-51b-1679 | | | | Volume
| 51 | |
| 3 | Author
| Georg Ziegler, Willi Kantlehner | Requires cookie* | | | Title
| Orthoamides, LVI [1]. A New Method of Wide Scope for the Preparation of Aryl Formates | | | | Abstract
| 26 are prepared by formylation of hydroxyarenes 3a-u, 25 with /V,Af-diformylacetamide (1) or triformamide (2), respectively, in fairly good yields. The reactions can be catalyzed by sodium diformamide or praseodymium(III) triflate. The thiolformate 28 was obtained analogously from 1-thionaphthol (27). | | | |
Reference
| Z. Naturforsch. 56b, 1172—1177 (2001); received July 13 2001 | | | |
Published
| 2001 | | | |
Keywords
| Aryl Formates, Formylation, Hydroxyarenes Aryl formates 4a-u, 6 | | | |
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| default:Reihe_B/56/ZNB-2001-56b-1172.pdf | | | | Identifier
| ZNB-2001-56b-1172 | | | | Volume
| 56 | |
| 4 | Author
| V.Salas Reyes3, C. Aguilerab | Requires cookie* | | | Title
| Synthesis and Characterization of Copper(II) and Nickel(II) Complexes Derived from «-Substituted Malondialdehydes | | | | Abstract
| The synthesis and characterization of two series of novel bis(4'-alkyloxyphenyl)m alondi-aldehydes of copper(II) and nickel(II), (R=C"H2"+1, n = 9, 10, 11, 12) from 2-(4'-hydroxy-phenyl)-3-dimethylamino acrolein is described. | | | |
Reference
| Z. Naturforsch. 50b, 205 (1995); received September 28 1994 | | | |
Published
| 1995 | | | |
Keywords
| M alondialdehyde, Acroleins, Formylation, M etallom esogen, Liquid Crystal | | | |
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| default:Reihe_B/50/ZNB-1995-50b-0205.pdf | | | | Identifier
| ZNB-1995-50b-0205 | | | | Volume
| 50 | |
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