{"id":1033,"date":"2025-09-17T17:23:37","date_gmt":"2025-09-17T10:23:37","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=1033"},"modified":"2025-11-15T13:11:29","modified_gmt":"2025-11-15T06:11:29","slug":"2-4-dichlorobenzyl-alcohol","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/2-4-dichlorobenzyl-alcohol\/","title":{"rendered":"2,4-Dichlorobenzyl Alcohol"},"content":{"rendered":"

\n

(Ph. Eur. monograph 2410)<\/p>\n

C7H6Cl2O 177.0 1777-82-8<\/p>\n<\/div>\n

\n

DEFINITION<\/h2>\n
(2,4-Dichlorophenyl)methanol.<\/p>\n

Content<\/h3>\n
98.0 per cent to 102.0 per cent (anhydrous substance).<\/p>\n

CHARACTERS<\/h2>\n

Appearance<\/h3>\n
White or almost white, crystalline powder.<\/p>\n

Solubility<\/h3>\n
Very slightly soluble in water, very soluble in ethanol (96 per cent).<\/p>\n

mp<\/h3>\n
About 59 \u00b0C.<\/p>\n

IDENTIFICATION<\/h2>\n
Infrared absorption spectrophotometry (2.2.24).<\/p>\n
Comparison 2,4-dichlorobenzyl alcohol CRS.<\/p>\n

TESTS<\/h2>\n

Related substances<\/h3>\n
Liquid chromatography (2.2.29).<\/p>\n
Solvent mixture: acetonitrile R1, water R (50:50 V\/V).<\/p>\n
Buffer solution: Dissolve 0.68 g of potassium dihydrogen phosphate R in 900 mL of water R, adjust to pH 3.0 with phosphoric acid R and dilute to 1000.0 mL with water R.<\/p>\n
Test solution (a): Dissolve 0.100 g of the substance to be examined in 10.0 mL of acetonitrile R1 and dilute to 50.0 mL with the solvent mixture.<\/p>\n
Test solution (b): Dilute 5.0 mL of test solution (a) to 50.0 mL with the solvent mixture.<\/p>\n
Reference solution (a): Dilute 1.0 mL of test solution (a) to 100.0 mL with the solvent mixture. Dilute 1.0 mL of this solution to 10.0 mL with the solvent mixture.<\/p>\n
Reference solution (b): Dissolve 20.0 mg of 2,4-dichlorobenzyl alcohol impurity A CRS and 20.0 mg of 2,4-dichlorobenzyl alcohol impurity C CRS in 100.0 mL of acetonitrile R1. Dilute 1.0 mL of the solution to 100.0 mL with the solvent mixture.<\/p>\n
Reference solution (c): Dissolve 0.100 g of 2,4-dichlorobenzyl alcohol CRS in 10.0 mL of acetonitrile R1 and dilute to 50.0 mL with the solvent mixture. Dilute 5.0 mL of the solution to 50.0 mL with the solvent mixture.<\/p>\n
Column:<\/p>\n
\u2014 size: l = 0.15 m, \u00d8 = 4.6 mm;<\/p>\n
\u2014 stationary phase: end-capped octadecylsilyl silica gel for chromatography R (5 \u03bcm);<\/p>\n
\u2014 temperature: 30 \u00b0C.<\/p>\n
Mobile phase:<\/p>\n
\u2014 mobile phase A: methanol R2, acetonitrile R1, buffer solution (20:30:50 V\/V\/V);<\/p>\n
\u2014 mobile phase B: acetonitrile R1;<\/p>\n\n\n\n\n\n\n
Time
\n(min)<\/td>\n Mobile phase A
\n(per cent V\/V)<\/td>\n Mobile phase B
\n(per cent V\/V)<\/td>\n<\/tr>\n
0 – 7<\/td>\n 100<\/td>\n 0<\/td>\n<\/tr>\n
7 – 17<\/td>\n 100 \u2192 20<\/td>\n \u00a00 \u2192 80<\/td>\n<\/tr>\n
17 – 30<\/td>\n 20<\/td>\n 80<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Flow rate: 1.2 mL\/min.<\/p>\n
Detection: Spectrophotometer at 214 nm.<\/p>\n
Injection: 10 \u03bcL of test solution (a) and reference solutions (a) and (b).<\/p>\n
Relative retention: With reference to 2,4-dichlorobenzyl alcohol (retention time = about 7 min): impurity C = about 0.87; impurity A = about 0.91.<\/p>\n
System suitability: Reference solution (b):<\/p>\n
\u2014 peak-to-valley ratio: minimum 4, where Hp = height above the baseline of the peak due to impurity C and Hv = height above the baseline of the lowest point of the curve separating this peak from the peak due to impurity A.<\/p>\n
Calculation of percentage contents:<\/p>\n
\u2014 for each impurity, use the concentration of 2,4-dichlorobenzyl alcohol in reference solution (a).<\/p>\n
Limits:<\/p>\n
\u2014 unspecified impurities: for each impurity, maximum 0.10 per cent;<\/p>\n
\u2014 total: maximum 0.3 per cent;<\/p>\n
\u2014 reporting threshold: 0.05 per cent.<\/p>\n
Water (2.5.32)<\/h4>\n
Maximum 0.2 per cent, determined on 0.500 g using the evaporation technique:<\/p>\n
\u2014 temperature: 120 \u00b0C.<\/p>\n
Sulfated ash (2.4.14)<\/h4>\n
Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n
ASSAY<\/h2>\n
Liquid chromatography (2.2.29) as described in the test for related substances with the following modification.<\/p>\n
Injection: Test solution (b) and reference solution (c).<\/p>\n
Calculate the percentage content of C7H6Cl2O taking into account the assigned content of 2,4 dichlorobenzyl alcohol CRS.<\/p>\n
IMPURITIES<\/h2>\n
Other detectable impurities (the following substances would, if present at a sufficient level, be detected by one or other of the tests in the monograph. They are limited by the general acceptance criterion for other\/unspecified impurities and\/or by the general monograph Substances for pharmaceutical use (2034). It is therefore not necessary to identify these impurities for demonstration of compliance. See also 5.10. Control of impurities in substances for pharmaceutical use) A, B, C, D, E, F, G.<\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
A. (2,5-dichlorophenyl)methanol,<\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
B. (2,6-dichlorophenyl)methanol,<\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
C. (3,4-dichlorophenyl)methanol,<\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
D. 2,4-dichlorobenzyl acetate,<\/span><\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
E. 2,4-dichlorobenzoic acid,<\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
F. 2,4-dichlorobenzaldehyde,<\/p>\n
$\"2,4-Dichlorobenzyl$ <\/p>\n
G. 1,1\u02b9-(oxydimethylene)bis(2,4-dichlorobenzene).<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
(Ph. Eur. monograph 2410) C7H6Cl2O 177.0 1777-82-8 DEFINITION (2,4-Dichlorophenyl)methanol. Content 98.0 per cent to 102.0 per cent (anhydrous substance). CHARACTERS Appearance White or almost white, crystalline powder. Solubility Very slightly soluble in water, very soluble in ethanol (96 per cent). mp About 59 \u00b0C. IDENTIFICATION Infrared absorption spectrophotometry (2.2.24). Comparison 2,4-dichlorobenzyl alcohol CRS. TESTS Related…<\/p>\n","protected":false},"author":3,"featured_media":1718,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-1033","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medicinal-substances"],"acf":[],"_links":{"self":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/1033","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=1033"}],"version-history":[{"count":6,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/1033\/revisions"}],"predecessor-version":[{"id":6648,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/1033\/revisions\/6648"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/1718"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=1033"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=1033"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=1033"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}