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"Methyl vinyl ether is an organic compound with the chemical formula CH3OCH=CH2. A colorless gas, it is the simplest enol ether. It is used as a synthetic building block, as is the related compound ethyl vinyl ether (a liquid at room temperature). Preparation Methyl vinyl ether can be made by reaction of acetylene and methanol in presence of a base. Reactions The alkene portion of the molecule is reactive in many ways. It is prone to polymerization, leading to formation of polyvinyl ethers. Polymerization is typically initiated with Lewis acids such as boron trifluoride. This mode of reactivity is analogous to the way vinyl acetate and vinyl chloride can be polymerized to form polyvinyl acetate and polyvinyl chloride, respectively. Methyl vinyl ether also participates in [4+2] cycloaddition reactions. Its reaction with acrolein is the first step in the commercial synthesis of glutaraldehyde. The alkene can be deprotonated at the vinyl carbon adjacent to the oxygen. In particular, this approach allows the synthesis of a variety of acyl derivatives of silicon, germanium, and tin that cannot be made easily by other routes. Toxicity The toxicity of vinyl ethers has been heavily investigated because divinyl ether has been used as an anesthetic. The acute LD50 for methyl vinyl ether is greater than 4 g/kg (rats, oral). References Category:Ethers Category:Vinyl compounds "
"Temnora atrofasciata is a moth of the family Sphingidae. It is known from Forests from western Africa to Congo and Uganda, with an apparently isolated population in the Usambara Mountains. The length of the forewings is about 22 mm for males and 24 mm for females. The forewings are fairly broad. The body and forewings are brown. There is a broad dark brown band running from the tornus to the costa. It is straight and well defined proximally, but irregular and strongly indented distally. The apical area is paler than the basal area. The hindwings are very dark brown, but slightly paler at the costa. The abdominal tufts are buff. The ground colour of females is darker and the wide dark band is much less contrasting. This dark band merges with the paler apical area distally. References Category:Temnora Category:Moths described in 1889 Category:Insects of Uganda Category:Insects of West Africa Category:Fauna of the Republic of the Congo Category:Fauna of Gabon Category:Insects of Tanzania Category:Moths of Africa "
"Irving Albert Leonard (December 1, 1896 in New Haven, Connecticut – October 1, 1996 in Alexandria, Virginia) was an American historian and translator, specialising in Hispanic history and art. His best known publications are Books of the Brave (1949) and Baroque Times in Old Mexico: Seventeenth-Century Persons, Places and Practices (1959), which won the Conference on Latin American History award for the best book in English. Books of the Brave, a valuable account of the introduction of literary culture to Spain's New World, was updated in 1992. He had many papers published in the American Historical Review and the Hispanic American Historical Review, such as A Frontier Library, 1799 (Feb. 1943, vol. 23, no. 1, p. 21–51). In 1960, Leonard served as chair of the Conference on Latin American History, the professional organization of Latin American historians. References Category:20th- century American historians Category:American translators Category:Historians of the Hispanic world Category:1896 births Category:1962 deaths Category:Writers from New Haven, Connecticut Category:Historians of Mexico Category:20th-century translators "