Name | 4-Chlorobenzaldehyde |
Synonyms | PCAD 4-Chlorobenzaldehyde P-CHLOROBENZALDEHYDE p-Chlorobenzaldehyde p-chloro-benzaldehyd benzaldehyde,-chloro- 4-Chloro Benzaldehyde Benzaldehyde,4-chloro- para-chlorobenzaldehyde 4-chloro benzalolehyole 4-chlorobenzoic aldehyde p-chlorobenzenecarboxaldehyde p-Chlorobenzaldehyde 4-Chlorobenzaldehyde |
CAS | 104-88-1 |
EINECS | 203-247-4 |
InChI | InChI=1/C7H5ClO/c8-7-3-1-6(5-9)2-4-7/h1-5H |
InChIKey | AVPYQKSLYISFPO-UHFFFAOYSA-N |
Molecular Formula | C7H5ClO |
Molar Mass | 140.57 |
Density | 1.196 |
Melting Point | 46 °C |
Boling Point | 213-214℃ |
Flash Point | 52°F |
Water Solubility | 935 mg/L (20 ºC) |
Solubility | 935mg/l |
Vapor Presure | 8.75 atm ( 21 °C) |
Vapor Density | 0.6 (vs air) |
Appearance | White solid |
Color | White to pale yellow |
BRN | 385858 |
Storage Condition | Store below +30°C. |
Stability | Stable, but air and light-sensitive. Incompatible with strong bases, strong reducing agents, strong oxidizing agents. |
Sensitive | Air Sensitive |
Refractive Index | 1.5550 (estimate) |
MDL | MFCD00003379 |
Physical and Chemical Properties | Properties of colorless crystals soluble in ethanol, ether and benzene, soluble in water, acetone. Can volatilize with water vapor |
Use | Mainly used in the manufacture of sedatives fennerol, aminophenylbutyric acid and other pharmaceutical raw materials and intermediates, in the pesticide used to produce chlorine cinnamaldehyde, herbicide powder, etc |
Risk Codes | R22 - Harmful if swallowed R36/37/38 - Irritating to eyes, respiratory system and skin. R51/53 - Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. R36/38 - Irritating to eyes and skin. |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. S37/39 - Wear suitable gloves and eye/face protection S36 - Wear suitable protective clothing. |
UN IDs | UN 1219 3/PG 2 |
WGK Germany | 2 |
RTECS | CU5076000 |
FLUKA BRAND F CODES | 8-9 |
TSCA | Yes |
HS Code | 29130000 |
Hazard Class | 9 |
Packing Group | III |
Toxicity | LD50 orally in Rabbit: 840 mg/kg LD50 dermal Rat 5000 mg/kg |
Raw Materials | 4-Chlorotoluene 4-Chlorotoluene |
Downstream Products | uniconazole |
LogP | 2.34 at 25℃ and pH7 |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
p-chlorobenzaldehyde | p-chlorobenzaldehyde is also known as 4-chlorobenzaldehyde. Colorless flake crystals to light yellow powder. Molecular weight 140.57. Melting point 47.5 ℃. Boiling point 213~214 ℃. Relative density 1.196 (61/4 ℃). The refractive index is 1.5552 (61 ℃). Flash point 87 ℃. Insoluble in water, soluble in ethanol, ether, benzene, soluble in water, acetone. Can volatilize with water vapor. Used as an intermediate in medicine and dyes, used in the manufacture of fenalol, aminophenylaminobutyric acid, etc. It is obtained by chlorination and hydrolysis of p-chlorotoluene. It can also be obtained by oxidation of p-chlorotoluene manganese dioxide. It can also be prepared by air oxidation of p-chlorotoluene. Preparation of plant growth regulator paclobutrazol: using p-chlorobenzaldehyde and 2, 2-dimethyl-3-butanone as raw materials, react in sodium hydroxide and tert-butanol solution to generate 1-(2, 2-dimethyl-3-keto-4-pentene) p-chlorobenzene, in ethyl acetate solution, nickel as a catalyst, hydrogenated at high temperature to generate 1-(2, 2-Dimethyl-3-pentanone) p-chlorobenzene, in carbon tetrachloride solution, add bromine to generate 1-(2, 2-dimethyl-4-bromo-3-pentanone) p-chlorobenzene, Further react with 1,2, 4-triazole in acetone solution, and finally in the methanol solution of sodium borohydride, paclobutrazol is generated. Baclofen is used as a skeletal muscle relaxant and antispasmodic agent for the spine. The condensation of p-chlorobenzaldehyde and ethyl acetoacetate produces p-chlorophenylene-bis-acetoacetate. Heat hydrolysis yields p-chlorophenyl glutaric acid. Paired chlorophenyl glutaric anhydride was produced by the anhydride dehydration ring. Then amination with concentrated ammonia to generate p-chlorophenyl glutaric acid amide, which is finally obtained by ring opening and degradation. |
Uses | p-chlorobenzaldehyde is an intermediate of the fungicide tebuconazole, the plant growth regulator uniconazole, and an intermediate of the insecticide chlorfenapyril. It is used in medicine as an intermediate of fenaluine and benzoate, and also a dye intermediate. used to make sedative drug fenalu, dye acid brilliant blue 6B, etc. mainly used to make sedative drug fenalu, aminophenylbutyric acid and other pharmaceutical raw materials and intermediates, used to produce chlorocinnamaldehyde in pesticides, herbicidosis, etc. used in organic synthesis medicine, dye intermediates, used to make fenalu, aminophenylaminobutyric acid, etc. Organic synthesis, manufacturing triphenylmethane and intermediates related dyes. Medicine; used in the manufacture of fenalol; aminophenyl aminobutyric acid, etc. |
production method | (1) obtained by chlorination and hydrolysis of p-chlorotoluene: add p-chlorotoluene and phosphorus trichloride to the reaction pot, raise the temperature to 155 ℃ under light, and introduce chlorine. Control the temperature at 160-170 ℃, pass chlorine to the calculated amount, and obtain the chlorination solution. It is added into concentrated sulfuric acid under stirring and stirred at normal temperature for 5 hours. Let it stand and layer, take the lower liquid and crystallize in ice water, cool to below 5 ℃ and filter. The filter cake is washed with ice water to obtain crude products, distilled under reduced pressure, and the finished product is obtained by collecting the fraction at 108-111 ℃(3.33kPa). (2) p-chlorotoluene manganese dioxide oxidation method: first add p-chlorotoluene to the reaction pot, then add 70% sulfuric acid, and slowly add manganese dioxide below 70 ℃. After adding, react for 0.5h, and then distill with steam. In addition, p-chlorobenzaldehyde can also be obtained by air oxidation of p-chlorotoluene. the preparation methods are commonly used as follows. The light reaction method puts p-chlorotoluene into the reactor equipped with ultraviolet lamp, and introduces chlorine gas at the reaction temperature of 60~100 ℃ for reaction. The amount of chlorine gas is 1 ∶ 1.5 in the molar ratio of p-chlorotoluene and chlorine gas. The depth of chlorine gas can be controlled by GC method. The reaction products include p-chlorobenzyl dichloride, 4-α,α,α-tetrachlorotoluene. If the depth of chlorine gas is large, the amount of p-chlorobenzyl chloride is small, and 4-α,α,α-tetrachlorotoluene is about 8%, and the above three components are separated by rectification. The mixture of 4-chlorobenzylidene dichloride and 4-α,α,α-tetrachlorotoluene can be hydrolyzed in the presence of catalysts FeCl3, ZnCl2, SnCl4 and metal oxides. The reaction temperature is 110~140 ℃, water is added to react for 4 hours, and the reaction end point is controlled by GC method. Then, under the protection of nitrogen, the components of 124 ℃/5.4kPa are collected as p-chlorobenzaldehyde, and the purity can reach 99%, the yield is above 93% (calculated as 4-chlorobenzylidene dichloride). Azobisisobutyronitrile catalytic chlorination method to add p-chlorotoluene into the reactor, heating to 160 ℃, adding azobisisobutyronitrile as catalyst, introducing chlorine gas for reaction, controlling the reaction end point by GC method, controlling not to generate 4-α,α,α-tetrachlorotoluene, then vacuum distillation, collecting 116~126 ℃/3kPa fraction, the yield is 87%, the former fraction p-chlorotoluene and p-chlorobenzyl chloride are recovered and used. The obtained 4-chlorobenzylidene dichloride was put into a reactor, and SnCl2 and appropriate water were added to react under reflux for 4h. After treatment, white crystals were obtained as products with 96% purity and 94% yield. Urotropine hydrolysis method Add Urotropine and water to the reactor, add the reaction products of chlorinated p-chlorobenzyl and 4-chlorobenzylidene dichloride to the reaction bottle, and react at 60~100 ℃ for 30~60min. When the hydrolysis conversion rate of benzyl chloride is 99%, the end point of the reaction is obtained. After post-treatment, p-chlorobenzaldehyde is obtained with 99% purity and 93.82% yield. Manganese dioxide oxidation method uses p-chlorotoluene as raw material, in the presence of sulfuric acid, manganese dioxide as oxidant for oxidation, and then steam distillation to obtain p-chlorobenzaldehyde. This is a laboratory method. In addition to the above methods, there are also electro-chemical synthesis and catalytic oxidation methods, but these methods are difficult to industrialize, and some processes are not yet mature and need further research. The hydrolysis of 4-chlorobenzylidene dichloride can also be carried out with 65% nitric acid at 90 ℃. The purity of the product is also high, up to 99%, and the yield is 80%. In addition, chlorinated chlorine in the presence of phosphorus trichloride and then hydrolyzed in the presence of sulfuric acid can also obtain p-chlorobenzaldehyde, but the yield is lower and the process is older. For this reason, the best process for preparing p-chlorobenzaldehyde can choose p-chlorotoluene as the raw material, through the light chlorination reaction, control the depth of chlorination, and then use urotropine for hydrolysis reaction, which can achieve low investment and easy operation, Good product quality, high yield, etc. |
category | toxic substances |
toxicity classification | poisoning |
acute toxicity | oral-rat LD50: 1575 mg/kg; Oral-mouse LD50: 1400 mg/kg |
flammability hazard characteristics | thermal decomposition discharges toxic nitrogen oxides and chloride smoke |
storage and transportation characteristics | warehouse low temperature ventilation and drying |
fire extinguishing agent | water, carbon dioxide, foam, dry powder |
spontaneous combustion temperature | 302°C |