1978-21-8

Basic information

• Product Name: 1,4-Benzenedicarbonyl difluoride (9CI)
• Synonyms: 1,4-Benzenedicarbonyl difluoride (9CI)
• CAS NO: 1978-21-8
• Molecular Formula: C₈H₄F₂O₂
• Molecular Weight: 170.1129664
• Product Categories: ACIDHALIDE
• Mol File: 1978-21-8.mol
• Article Data: 4

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 1,4-Benzenedicarbonyl difluoride (9CI)(CAS DataBase Reference)
• NIST Chemistry Reference: 1,4-Benzenedicarbonyl difluoride (9CI)(1978-21-8)
• EPA Substance Registry System: 1,4-Benzenedicarbonyl difluoride (9CI)(1978-21-8)

Safety Data

• Hazardous Substances Data: 1978-21-8(Hazardous Substances Data)

Usage

Physical State

Colorless liquid

Usage

a. Monomers in the production of polyesters
b. Cross-linking agent in polymeric materials

Polyesters Produced

a. Polyethylene terephthalate (PET)
b. Polybutylene terephthalate (PBT)

Toxicity

Considered toxic

Health Hazards

a. Skin irritation
b. Eye irritation
c. Respiratory system irritation

Safety Measures

Appropriate safety measures should be taken when handling the compound

Upstream product

• 100-21-0 terephthalic acid 
• 127410-75-7 4-Fluorocarbonyl-benzoic acid 
• 201230-82-2 carbon monoxide 
• 106-37-6 1.4-dibromobenzene 
• 120-61-6 1,4-benzenedicarboxylic acid dimethyl ester 

Downstream Products

• 2182-77-6 2-(4-methoxycarbonylphenyl)benzothiazole 
• 20000-53-7 2-(4-methoxycarbonylphenyl)-1,3-benzoxazole 
• 100880-52-2 methyl 4‐(1H‐benzo[d]imidazol‐2‐yl)benzoate 

Relevant articles and documents

Synthesis of Acyl Fluorides from Carboxylic Acids Using NaF-Assisted Deoxofluorination with XtalFluor-E

The synthesis of acyl fluorides using the deoxofluorination reaction of carboxylic acids using XtalFluor-E is described. This transformation, assisted by a catalytic amount of NaF, occurs at room temperature in EtOAc, where XtalFluor-E behaves as the activating agent and the fluoride source. A wide range of acyl fluorides were obtained in moderate to excellent yields (36-99%) after a simple filtration on a pad of silica gel. We also demonstrated that sequential deoxofluorination/amidation was possible.

Catalytic Acid Fluoride Synthesis via Carbonylation of Organic Bromides in the Presence Potassium Fluoride

Various aryl bromides were carbonylated under an atmospheric pressure of carbon monoxide in DMF in the presence of potassium fluoride to give aroyl fluorides in excellent yields.The carbonylation was promoted by the addition of phase transfer catalysts, but the contamination with water reduced the selectivity.