83881-51-0Relevant articles and documents
Process for obtaining cetirizine dihydrochloride
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Page/Page column 4; 5, (2009/02/11)
Process for the synthesis of cetirizine dihydrochloride, wherein (a) a solution of {2-[4-(α-phenyl-p-chlorobenzyl)piperazin-1-yl]}ethanol in 1-7 volumes, referred to the weight of {2-[4-(α-phenyl-p-chlorobenzyl)piperazin-1-yl]}ethanol, of an organic solvent having a boiling point higher than 90° C. and being chosen from the group consisting of aliphatic, cycloalifatic or aromatic solvents is provided, whereafter(b) per equivalent of {2-[4-(α-phenyl-p-chlorobenzyl)piperazin-1-yl]}ethanol employed, 1-2 equivalents of a metal haloacetate or of haloacetic acid, as well as 3-7 equivalents of an alkaly metal hydroxyde are added to the solution as per (a), providing a reaction mixture, where 0.05-0.3 volumes, referred to the weight of {2-[4-(α-phenyl-p-chlorobenzyl)piperazin-1-yl]}ethanol employed, of water and 0.1-1.2 volumes, referred to the weight of {2-[4-(α-phenyl-p-chlorobenzyl)piperazin-1-yl]}ethanol employed, of a polar aprotic, water miscible solvent are added, keeping the internal temperature of the reaction mixture below 60° C., whereafter(c) the cetirizine base formed within the reaction mixture is converted into its dihydrochloride salt and isolated as such.
2-[2-[4-[(4-CHLOROPHENYL) PHENYLMETHYL]-1-PIPERAZINYL]ETHOXY]ACETIC ACID MONOHYDROCHLORIDE AS ANTI-ALLERGENIC COMPOUND AND PROCESS FOR ITS PRODUCTION
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Page 16-17, (2008/06/13)
An anti-allergenic compound having therapeutic value and a process for its manufacture. The disclosure is directed to 2-[2-[4-[(4-chlorophenyl)phenylmethyl]-1piperazinyl]ethoxy]acetic acid monohydrochloride, to compositions containing 2-[2-[4-[(4chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetic acid monohydrochloride, and to a process for the preparation of 2-[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetic acid monohydrochloride.
A PROCESS FOR THE PREPARATION OF 2- 2- 4-(DIPHENYLMETHYL)-1-PIPERAZINYL]ETHOXY ACETIC ACID COMPOUNDS OR SALTS THEREOF
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Page/Page column 5, (2008/06/13)
2-{2-[4-(diphenylmethyl)-1-piperazinyl]ethoxy}acetic acid compounds of general formula (I) wherein R and R independently represent hydrogen, halogen, lower alkoxy or trifluoromethyl, or salts thereof are prepared by reacting a corresponding 2-[4-(diphenylmethyl)-1-piperazinyl]ethanol with a 2-substituted acetaldehyde dialkylacetal in the presence of a proton acceptor in an inert solvent to form a corresponding diphenylmethylpiperazinoethoxyacetaldehyde dialkylacetal, and thereafter hydrolysing the acetal to the corresponding aldehyde, catalysed by a proton donor, and then oxidising the aldehyde to the acid (I) by means of a suitable oxidation agent. If desired, the acid (I) is converted into a salt thereof. The process is cheap, easy to perform and gives a high yield. The most interesting compound is 2-{2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]-ethoxy}acetic acid in the form of its dihydrochloride known by the generic name of cetirizine. The 2-{2-[4-(diphenylmethyl)-1-piperazinyl]ethoxy}acetaldehyde compounds and their dialkylacetals are novel compounds.