145701-23-1

Basic information

• Product Name: Florasulam
• Synonyms: [1,2,4]Triazolo[1,5-c]pyrimidine-2-sulfonamide, N-(2,6-difluorophenyl)-8-fluoro-5-methoxy-; de-570; florasulam (bsi,iso); florasulam (ISO) 2',6',8-trifluoro-5-methoxy-5-triazolo[1,5-c] pyrimidine-2-sulfonanilide; N-(2,6-difluorophenyl)-8-fluoro-5-methoxy[1,2,4]triazolo[1,5-c]pyrimidine-2-sulfonamide
• CAS NO: 145701-23-1
• Molecular Formula: C₁₂H₈F₃N₅O₃S
• Molecular Weight: 359.2838
• Product Categories: Herbicide;NULL
• Mol File: 145701-23-1.mol
• Article Data: 7

Chemical Properties

• Melting Point: 220-221° (dec) (Van Heertum); also reported as 193.5-230.5° (Thompson)
• Density: 1.757g/cm³
• Refractive Index: 1.676
• Storage Temp.: 0-6°C
• PKA: 4.54(at 25℃)
• CAS DataBase Reference: Florasulam(CAS DataBase Reference)
• NIST Chemistry Reference: Florasulam(145701-23-1)
• EPA Substance Registry System: Florasulam(145701-23-1)

Safety Data

• Hazard Codes: N:
• Statements: R50/53:
• Safety Statements: S60-61:
• RIDADR: UN 3077 9 / PGIII
• WGK Germany: 2
• Hazardous Substances Data: 145701-23-1(Hazardous Substances Data)

Usage

Description

Florasulam is a kind of selective triazolopyrimidine sulfonanilide post-emergent herbicide. It is absorbed by the foliage or roots of the plants. It acts as a systemic herbicide, being able to disrupt the internal growth processes of the weeds and causes their death in several weeks. It can be used for the control of broadleaf weeds in cereals. Its mechanism of action is through inhibiting the acetolactate synthase (ALS) in plants. The enzyme is present in the chloroplast and participates into the biosynthesis of branch chain amino acids such as valine, leucine and isoleucine. Through this mechanism, it can suppress plant cell division, plant growth and ultimately cause plant death.

References

http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_07cf/0901b803807cfdd2.pdf?filepath=productsafety/pdfs/noreg/233-00436.pdf&fromPage=GetDoc http://www.agropages.com/AgroData/Detail-640.htm

Uses

Herbicide.

Upstream product

• 1801-06-5 2-methoxy-4-chloro-5-fluoropyrimidine 
• 147150-78-5 2-chlorosulfonyl-8-fluoro-5-methoxy-[1,2,4]triazolo[1,5-c]pyrimidine 
• 5509-65-9 2,6-difluoroaniline 
• 57-55-6 propylene glycol 

Relevant articles and documents

Preparation method of triazolopyrimidine herbicide

The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of a triazolopyrimidine herbicide. The preparation method specifically comprises thefollowing steps: a) reacting a compound with the structure represented by formula (I) with thiosemicarbazide, and then isomerizing under an alkaline condition to obtain a compound with the structurerepresented by formula (II); b) carrying out a diazotization reaction on the compound of the formula (II) and sodium nitrite, and then mixing and reacting with sodium hydrogen sulfite and chloride toobtain a compound with the structure represented by formula (III), wherein the chloride comprises copper chloride and/or cuprous chloride; and c) reacting the compound of the formula (III) with a compound with the structure represented by formula (IV) to obtain the triazolopyrimidine herbicide with the structure represented by formula (V). The preparation method provided by the invention has the advantages of mild reaction conditions, low safety risk and good environmental friendliness.

METHOD OF PREPARATION OF FLORASULAM

The present disclosure concerns a method for preparing florasulam which involves treating a solution of 2,6-difluoroaniline in 1,2-propylene glycol with: a) sulfonyl chloride III and then b) a base to provide, after workup and isolation, florasulam (I) in yields of about 65-85%. The treatment of 2,6-difluoroaniline with sulfonyl chloride III and the base are conducted by controlled additions.

Preparation of n-arylarylsulfonamide compounds

N-(substituted aryl)?1,2,4!triazoloazinesulfonamide compounds, such as N-(2,6-difluorophenyl)-8-fluoro-5-methoxy?1,2,4!triazolo?1,5-c!pyrimidine-2-sulfonamide, were prepared at a good reaction rate and in good yield by the reaction of a chlorosulfonyl?1,2,4!triazoloazine compound, such as 2-chlorosulfonyl-8-fluoro-5-methoxy?1,2,4!triazolo?1,5-c!pyrimidine, and an arylamine compound, such as 2,6-difluoroaniline, in an organic medium containing a relatively acidic alcohol, such as propylene glycol or 2,2,2-trifluoroethanol.