The characteristics of maleimide


Maleimide PEG

Maleimide is an organic substance with chemical formula C4H3NO2, flaky crystal, easy to sublime, soluble in water, ether and ethanol.

Maleimide Features:

Alias: Maleimide, 2,5-Pyrroledione
Chemical formula: C4H3NO2
Molecular weight: 97.07
CAS: 541-59-3
EINECS: 208-787-4
Melting point: 92℃~94℃
Boiling point: 97 ℃
water solubility: soluble
Density: 1.2493 g/cm³
Appearance: flaky crystal
Refractive index: 1.4543
Flash point: 97 ℃
Application: Organic Synthesis
Hazard symbols: R36/37/38, R25, R43
UN Dangerous Goods Number: UN 2923 8/PG 2

Preparation method of maleimide:

It is derived from the reaction of pyrrole with potassium dichromate. 1177g of potassium dichromate was dissolved in 1200ml of water and 712ml of concentrated sulfuric acid, heated to 35°C, 54g of pyrrole was slowly added under stirring, and the reaction temperature did not exceed 50°C. After the addition is completed, the reaction is kept at 40-50 °C until there is no pyrrole odor. After cooling, a small amount of tar produced by the reaction was filtered off with glass wool, and the filter residue was washed with hot water. The filtrate and washings were extracted with ether, the extract was dried over anhydrous sodium sulfate, and the ether was recovered by evaporation to obtain crude crystals (slightly yellow). By vacuum sublimation, 7g of pure white crystal product can be obtained.

Maleimide application areas:

for organic synthesis. Rhodium-Catalyzed Arylation Combination with Arylboronic Acids. It is an important raw material for the synthesis of the leukemia drug Midostaurin.

Maleimide storage and transportation:

Store in a cool, dry place. Store in an airtight container.

Maleimide Safety Measures:

personal protection
Wear suitable protective eyewear or chemical safety goggles, OSHA’s Eye and Face Protection Regulations 29 CFR 1910.133 or European Standard EN166. Wear suitable gloves to prevent skin contact. Wear appropriate protective clothing to prevent skin contact. According to OSHA Respirator Regulations 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator if necessary. Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Avoid contact with skin and eyes. Avoid ingestion and inhalation.
Ingestion: Get medical attention. Wash mouth with water; Inhalation: Immediately from the scene to fresh air; Skin: For at least 15 minutes, while flushing skin with plenty of soap and water to remove contaminated clothing and shoes; Eyes: Flush with plenty of water for at least 15 minutes, Rinse eyes, lifting the upper and lower eyelids from time to time.

Maleimide fire protection measures:

Extinguishing Media: Fire extinguishing with water mist, dry powder, foam or carbon dioxide. Avoid using direct water to put out the fire, which may cause splashes of flammable liquids and spread the fire.
Fire-fighting precautions and protective measures: Firefighters must wear air-carrying respirators and full-body fire-fighting suits to put out the fire in the upwind direction. Move the container from the fire area to an open area as much as possible. Containers in fire must be evacuated immediately if they have discolored or emit sound from safety pressure relief devices. Isolate the accident scene and prohibit unrelated persons from entering. Contain and treat fire water to prevent environmental pollution.

Maleimide spill treatment:

Small spills: Collect spilled liquid in sealable containers whenever possible. Absorb with sand, activated carbon or other inert material and transfer to a safe place. Do not flush into sewers.
Large spills: Construct dikes or dig pits for containment. Close the drain. Cover with foam to inhibit evaporation. Transfer it to a tanker or a special collector with an explosion-proof pump, and recycle it or transport it to a waste disposal site for disposal.

Maleimide Toxicological Information:

Ingestion may cause irritation of the digestive tract. The toxicological properties of this substance have not been adequately investigated; inhalation can cause respiratory irritation. Skin irritation may result from skin contact, which may become apparent upon further contact; eye irritation may be caused by entry; in addition, flammable hydrogen gas may form in contact with metal.

AxisPharm offers high purity PEG Maleimide(Mal-PEG) linkers, which is a sulfhydryl (thiol/SH) group reactive PEG derivative used to selectively modify protein, peptide or any other surfaces with available sulfhydryl groups.
Maleimide PEG(Mal-PEG) allows efficient PEGylation of sulfhydryl groups at pH 6.5-7.5; the reaction of the maleimide group results in the formation of a thioether bond.