Methyl Vinyl Ether Hydrolysis

1 department of chemistry and chemical biology mcmaster university hamilton on canada.

Methyl vinyl ether hydrolysis.

Occupational exposure to vinyl methyl ether may occur through inhalation and dermal contact with this compound at workplaces where vinyl methyl ether is produced or used. The resulting oxonium ion then decomposes into methanol and a relatively stable tert butyl cation the latter is then attacked by a nucleophile halide here bromide. Some commercially important vinyl ethers include ethyl n butyl isobutyl ethylhexyl dodecyl octadecyl and cyclohexyl vinylether. Poly methyl vinyl ether alt maleic acid polymers for cell encapsulation.

Methyl vinyl ether is reacted with maleic anhydride to produce the strictly alternating copolymer of various molecular weights in the anhydride form. Rates of hydrolysis of the vinyl ether functional groups of z and e β methoxyacrylic acid and z and e β methoxymethacrylic acid and their methyl esters were measured in aqueous perchloric acid solution additional rate measurements were also made for one substrate z β methoxymethacrylic acid in buffer solutions down to ph 7 and a rate profile was constructed. Wislicenus who was the first to prepare ethyl vinyl ether also reported on the halogenation hydrolysis and polymerization of this simple enol ether. 1 instead you need to use the fact that an enol ether is very much like an enol.

Hydrolysis is expected based on hydrolysis half lives of 9 5 hours 40 days and 10 9 years at ph 5 6 and 9 respectively for structurally similar butyl vinyl ether. Other manufacturers of vinyl ether polymers and copolymers are ashland and idemitsu kosan. It is nucleophilic on the α carbon and you can protonate it on that carbon almost like you are tautomerising an enol back to a ketone. Enol ethers are intermediate in their chemical properties between olefins and enamines.

S n 1 ether cleavage. The vinyl carbonate 13 152 gives only copolymerization the ketene acetal 11 153 and the methyl vinyl ether 14 152 give both copolymerization and chain transfer in styrene polymerization whereas with the benzyl vinyl ethers 12 153 15 8 and 16 18 151 chain transfer is the only reaction detected. The unimolecular s n 1 mechanism proceeds via a carbocation provided that the carbocation can be adequately stabilized. The anhydrides can also be readily converted into half esters by reacting with alcohols.

The main manufacturer of vinyl ether monomers and resins is basf. The anhydride is converted to the acid form by hydrolysis. In the example the oxygen atom in methyl tert butyl ether is reversibly protonated. Vinyl mathrm sp 2 cations are very unstable and an mathrm s n1 type dissociation of meoh is very unlikely.