64754-74-1

Upstream product

• 17757-70-9 2-methyl-N-phenyl-5,6-dihydro-1,4-oxathiine-3-carboxamide 4-oxide 
• 108-24-7 acetic anhydride 
• 110512-33-9 2,3-dichloro-2-methyl-1,4-oxathiin-3-carboxanilide 
• 5234-68-4 5,6-dihydro-2-methyl-N-phenyl-1,4-oxathiin-3-carboxamide 
• 75420-87-0 2,3-Diacetoxy-2-methyl-1,4-oxathiane-3-carboxanilide 

Downstream Products

• 180068-90-0 α-hydroxy-2-methyl-N-phenyl-1,3-oxathiolane-2-acetamide 

Relevant academic research and scientific papers

Phototransformation of carboxin in water. Toxicity of the pesticide and its sulfoxide to aquatic organisms

Sunlight exposure of aqueous suspensions of carboxin (1) causes its phototransformation to sulfoxide 2 and minor components. Similar effects are observed in the presence of humic acid or nitrate or at different pH values. Photoproducts 2-9 were isolated by Chromatographic techniques and/or identified by spectroscopic means. Carboxin 1 and its main photoproduct sulfoxide 2 were tested to evaluate acute toxicity to primary consumers typical of the aquatic environment: the rotifer Brachionus calyciflorus and two crustaceans, Daphnia magna and Thamnocephalus platyurus. Chronic tests comprised a producer, the alga Pseudokirchneriella subcapitata, and a consumer, the crustacean Ceriodaphnia dubia.

CONVERSION OF DIHYDRO-1,4-OXATHIIN-3-CARBOXAMIDE TO THE ISOMERIC DIHYDRO-1,4-OXATHIIN-2-CARBOXAMIDE

The preparation of isomeric dihydro-1,4-oxathiin (3) from the dihydro-1,4-oxathin (1) via dichloro-1,4-oxathiane (4) is described.Chlorination of 1 followed by treatment of the resulting dichloride (4) with aqueous acetone gave dihydroxy-1,4-oxathiin (5).The solvolysis to produce intermediate chlorohydrin (11) was favored relative to elimination reaction to give exomethylene compound (8).Dehydration of 5 followed by reduction afforded α-hydroxy-1,3-oxathiolane (2) which is a key compound to prepare the isomeric dihydro-1,4-oxathiin (3).The reason for more facile displacement of chlorine at C-2 in comparison with that at C-4 in 4 was also discussed.

Additive Pummerer-Initiated Functionalization of Allylic Methyl Groups in Acrylic Acid Derived Systems

Elucidation of reaction parameters for the conversion of the additive Pummerer product 2,3-bis(trifluoroacetoxy)-2-methyl-1,4-oxathiane-3-carboxanilide (2) to N-(trifluoroacetyl)-5,6-dihydro-2--1,4-oxathiin-3-carboxanilide (3) w