Patent EP0253191A1 successfully refreshed from Google Patents.
EP0253191A1
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EP
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Process for the preparation of (2,2)-Paracyclophane and derivatives thereof
Assignee: Montedison SpA
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Filing: 1987-06-29
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Granted: —
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Expires: 2007-06-29
Abstract
Abstract Process for the preparation of (2,2)-paracyclophane or derivatives thereof by the Hofmann elimination of p-methylbenzyl-trimethylammonium hydroxide or derivatives thereof, in an aqueous solution of an alkali metal hydroxide, wherein said elimination is carried out in the presence of a dialkylether or mono- and poly-ethylene glycols having the formula: R - O @CH2CH2O @ n R' (I) wherein R and R', which may be the same or different, represent alkyl groups having from 1 to 5 carbon atoms, and n is an integer from 1 to 5.
Inventors
- 👤 Giorgio Bornengo
- 👤 Alessandro Malacrida
- 👤 Stefano Campolmi
- 👤 Maurizio Augusto Beretta
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 08:42
CPC Classifications
C; C07; C07C; C07C13/00; C07C13/28; C07C13/32; C07C13/54; C07C13/605; C07C1/00; C07C1/32; C07C1/321; C07C1/323; C07C17/00; C07C17/26; C07C17/263; C07C2603/00; C07C2603/92
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
141 words
A process for preparing (2,2)-paracyclophane and derivatives thereof of the formula: wherein X is a halogen atom, an alkyl radical, an aralkyl radical, or a halo-aralkyl radical having up to 20 carbon atoms, and p is zero or an integer from 1 to 4, by the Hofmann elimination of p-methylbenzyl trimethyl-ammonium hydroxide or derivatives thereof of the formula: wherein X and p are the same as defined above, in an aqueous solution of an alkali metal hydroxide, characterized in that said Hofmann elimination is carried out in the presence of at least one di-alkylether of mono- and poly-ethylene glycols having the formula: R - O [ CH₂CH₂O ] n R' (I) wherein R and R', which may be the same or different, represent alkyl radicals having from 1 to 5 carbon atoms, and n is an integer from 1 to 5.
Claim 2
Dependent Claim
141 words
A process for preparing (2,2)-paracyclophane and derivatives thereof of the formula: wherein X is a halogen atom, an alkyl radical, an aralkyl radical, or a halo-aralkyl radical having up to 20 carbon atoms, and p is zero or an integer from 1 to 4, by the Hofmann elimination of p-methylbenzyl trimethyl-ammonium hydroxide or derivatives thereof of the formula: wherein X and p are the same as defined above, in an aqueous solution of an alkali metal hydroxide, characterized in that said Hofmann elimination is carried out in the presence of at least one di-alkylether of mono- and poly-ethylene glycols having the formula: R - O [ CH₂CH₂O ] n R' (I) wherein R and R', which may be the same or different, represent alkyl radicals having from 1 to 5 carbon atoms, and n is an integer from 1 to 5.
Claim 3
Dependent Claim
35 words
The process according to Claim 1, in which the p-methylbenzyltrimethylammonium hydroxide of formula (III) is prepared in situ from the corresponding halide by the action of the alkali metal hydroxide present in the reaction medium.
Claim 4
Dependent Claim
23 words
The process according to Claim 1 or 2, in which the ether of formula (I) is the di-ethylene-glycol-di-methyl ether or the tetra-ethylene-glycol-di-methyl ether.
Claim 5
Dependent Claim
27 words
The process according to any of the preceeding claims, in which the weight ratios: ether of formula (I)/p-methyl-benzyltrimethyl-ammonium hydroxide of formula (III) is between 2 and 50.
Claim 6
Dependent Claim
26 words
The process according to Claim 4, in which the weight ratios: ether of formula (I)/p-methyl benzyltrimethyl ammonium hydroxide of formula (III) is between 4 and 10.
Claim 7
Dependent Claim
56 words
The process according to any of the preceding claims, in which the molar ratio of the alkali metal hydroxide to p-methyl-benzyl timethyl ammonium hydroxide of formula (III) is between 1 and 10, and the concentration of the aqueous solution of the alkali metal hydroxide is maintained, during the Hofman elimination, between 15 and 35% by weight.
Claim 8
Dependent Claim
44 words
The process according to any of the preceding claims, in which the Hofmann elimination is carried out at a temperature between 50° and 150°C, preferably between 70°C and 120°C, and for a time of 1 to 40 hours, preferably of 2 to 10 hours.
Claim 9
Dependent Claim
31 words
The process according to any of the preceding claims, in which the Hofmann elimination is carried out in the presence of an inert organic solvent that is not miscible with water.
References Cited (Backward Citations)
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