Word: dimethyl
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Dates: during 1960-1969
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Acetylene, deuteroacetylene, methyl and dimethyl acetylenes are strongly chemisorbed on alumina even at room temperature. The first three can also exist in a weakly adsorbed state. The strongly held species are held perpendicular to the surface through the acetylenic hydrogens, except dimethyl acetylene, which is held parallel to the surface. All the weakly held acetylenes are held parallel to the surface. The sites responsible for the strong chemisorption of acetylenes are different from those responsible for the strong adsorption of dimethyl acetylene. Surprisingly, no strong chemisorption of either acetylene or dimethyl acetylene was observed with silica...
...Muggins has no direct evidence to prove his theory. He got the idea from a valuable research technique he recently developed for inducing cancers quickly in female rats (of a particular inbred strain), to which he gives a single feeding of 7.12-dimethyl-benz(a)anthracene. It works every time...
...those who care to try it themselves, the first sentence of Woodward's seven-page description of the synthesis, as reported to the Journal of the American Chemical Society, reads: "2 -(β, β-Dicyanovinyl)-3, 5-dimethyl-4-ethylpyrrole was converted by sulfuryl chloride in acetic acid at 55° to 2-(β, β-dicyanovinyl)-3-methyl-4-ethyl-5-chloromethylpyrrole [m.p. 189-192°], and thence, by condensation with 3-carbethoxy-4-methylpyrrole in hot aqueous etha-nolic hydrochloric acid to 3', 4-dimethyl-3-ethyl-4'-carbethoxy-5-(β, β-dicyanovinyl) dipyrrylmethane...