![]() 1,1,3,3-Tetramethyl-1,3-divinyldisiloxane exhibited a much higher reactivity than did the other vinylsilane compounds. No cleavage reaction, however, proceeded in the reaction of lithium diethylamide with vinylsilane compounds having a disiloxane linkage. In the reaction between lithium diethylamide and vinylsilane having an ethoxyl group, an addition reaction to the vinyl group and a cleavage reaction of the Si–O linkage proceeded concurrently. A vinylsilane compound having a 2-(dialkylamino)ethyl substituent, dimethylvinylsilane, showed unique reactivity toward lithium diethylamide, indicating that the β-nitrogen atom plays an important role regarding the reactivity of the vinyl group. This fact may be explained by a π-conjugation between the phenyl (or vinyl) and vinyl groups through an empty d-orbital of the Si atom. 10 −4 dm 3 mol −1 s −1], were higher than that of trialkyl-substituted vinylsilane. since idota reported lithium electrochemical activity with transition metal oxides, 1 the lithium reactive mechanism in these transition metal oxides has been proposed.10 −4 dm 3 mol −1 s −1] and dimethyldivinylsilane [ k (dimethyldivinylsilane cHx 50 ☌) = 14.8 ± 0.6 Lithium metal reacts vigorously with all the halogens to form lithium halides.dimethylphenylvinylsilane [ k (dimethylphenylvinylsilane cHx 50 ☌) = 14.8 ± 0.3 The reactivities of vinylsilane compounds having an aryl substituent, e.g. ![]() 10 −4 dm 3 mol −1 s −1] was found to be of the same order of magnitude as that of para-alkyl-substituted styrenes, such as 4-methylstyrene [ k (4-methylstyrene cHx 50 ☌) = 3.2.The reactivity of trimethylvinylsilane [rate constant k (trimethylvinylsilane cHx 50 ☌) = 2.9 ± 0.2 The reactivity of vinylsilane derivatives toward nucleophile was strongly influenced by the nature of the substituents on the Si atom. Kinetic studies concerning the addition reactions of lithium diethylamide (Et 2NLi) to several vinylsilane derivatives, such as H 2C=CH–Si(CH 3) 2X, and H 2C=CH–Si(CH 3) 2OSi(CH 3) 2X, were carried out.
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