Ethers, divinyl

The last step in the synthesis of divinyl ether (used as an anesthetic under the name Vinethene) involves heating CICH2CH2OCH2CH2CI with potassium hydroxide Show how you could prepare the necessary starting material CICH2CH2OCH2CH2CI from ethylene... 

Vinyl Ethers. The principal commercial vinyl ethers are methyl vinyl ether (methoxyethene, C H O) [107-25-5], ethyl vinyl ether (ethoxyethene, C HgO) [104-92-2], and butyl vinyl ether (1-ethenyloxybutane, C H 20) [111-34-2]. (See Table 8 for physical properties.) Others such as the isopropyl, isobutyl, hydroxybutyl, decyl, hexadecyl, and octadecyl ethers, as well as the divinyl ethers of butanediol and of triethylene glycol, have been offered as development chemicals (see Ethers). 

Similar polyacetals were prepared by BASF scientists from CO-aldehydic aUphatic carboxyUc acids (189,190) and by the addition of poly(hydroxycarboxyhc acid)s such as tartaric acid to divinyl ethers (191) as biodegradable detergent polymers. 

Although they lack commercial importance, many other poly(vinyl acetal)s have been synthesized. These include acetals made from vinyl acetate copolymerized with ethylene (43—46), propjiene (47), isobutjiene (47), acrylonitrile (48), acrolein (49), acrylates (50,47), aHyl ether (51), divinyl ether (52), maleates (53,54), vinyl chloride (55), diaHyl phthalate (56), and starch (graft copolymer) (47). 

Dioctyl ether Didecyl ether Methyl ethyl ether 1,2-Diethoxyethane 9.2 Unsaturated Ethers Divinyl ether... 

Heitz et al. (33) also described the preparation of polyvinyl acetate cross-linked with butanediol divinyl ether. The polymer is the base of the Merckogel series of size exclusion chromatography packings, and its hydrolyzed derivative, polyvinyl alcohol, is marketed as Fractogel and Toyopearls. 

A more complicated behaviour was obtained with divinyl ether due to the formation of both cyclic structures and pendent vinyl groups in the chain. The failure of such olefins as styrene and isopropenylbenzene to give copolymers with 2-fural-dehyde, and in fact to homopolymerize in its presence, was blamed on the strength of the complex formed between the initiator and the aldehyde, believed too stable to initiate polymerization. 

Geometric considerations would seem to dictate that 1,4- and 1,5-dicncs should not undergo cyclopolymerization readily. However, in the case of 1,4-dienes, a 5-hexenyl system is formed after one propagation step. Cyclization via 1,5-backbiling generates a second 5-hexenyl system. Homopolymerization of divinyl ether (22) is thought to involve such a bicyclization. The polymer contains a mixture of structures including that formed by the pathway shown in Scheme 4.18. 

In this section wc consider systems where the radical formed by propagation can eyclizc to yield a new propagating radical. Certain 1,4-dicncs undergo cyclocopolymerization with suitable olefins. For example, divinyl ether and MAH are proposed to undergo alternating copolymerization as illustrated in Scheme 4.19.167 These cyclo-copolymerizations can he quantitative only for the case of a strictly alternating copolymer. This can be achieved with certain electron donor-electron acceptor pairs, for example divinyl ether-maleic anhydride. 

Baden JM, Kelley M, Mazze Rl, et al. 1979. Mutagenicity of inhalation anaesthetics Trichloroethylene, divinyl ether, nitrous oxide, and cyclopropane. Br J Anaesth 51 417-421. 

Divinyl ether combusts in the presence of nitric acid within a millisecond. 

Methotrexate-7-Hydrazide and Divinyl Ether—Maleic Anhydride Conjugate Antitumor Activity in Mice... 

Material. Methotrexate-y-hydrazide was prepared by a modified procedure described by Rosowsky (14). Divinyl ether-maleic anhydride copolymer was purchased from Hercules Incorporated (Wilmington, DE) and had an average molecular weight of 11,400. Centriprep-10 concentrators were purchased from Amicon (Danvers, MA). 

Barricelli, L. L., u. O. Bastiansen The structure of divinyl ether. Acta... 

Divinyl ether is hypergolic with cone, nitric acid, ignition delay being 1 ms. 

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