Transition-Metal Reactions of Benzodisilacyclobutenes

在这篇文章中，我们报道了铂催化的等压取代苯并二硅环丁烯的反应。3，4-苯并-1，1，2，2-四(异丙基)-L，2-二硅-1-酰基-3-烯(1)与苯乙炔和1-己炔在200ﾟ℃下，在200ﾟ℃下催化反应24小时，得到两种类型的1：1目标产物，2-苯基和2-丁基取代的5，6-苯并-1，1，4，4-四(异丙基)-1，4-二硅基环己-2，5-二烯和2-亚甲基-4，2-取代5-苯并-1，1，3，3-四(异丙基)-1，3-二硅环-4烯。与甲苯基和二甲基苯基硅基乙炔反应，1得到2-(甲苯基)亚甲基和2-(二甲基苯基硅基)-亚甲基-4，5-苯并-1，1，3，3-四(异丙基)-1，3-二硅环戊烯-4-烯。I与三甲基硅基-乙炔的类似反应通过SP杂化的C-H键活化乙炔和苯并二硅环戊烯衍生物生成了加成物。1w…的反应与去苯乙炔反应生成2，3-二苯基-5，6-苯二硅环己烷-2，5-二烯衍生物，与甲基苯乙炔和2-己炔反应得到2-亚苄基和2-丁亚基-5，6-苯并-1，4-环硅烷-5-烯，以及苯二硅烷-2，5-二烯衍生物。用甲基(三甲基硅基)乙炔与1类似的反应合成了5，6-benzo-2-(trimethylsilyl)methylenedisilacyclohexene衍生物。我们还报道了苯并二(二硅环丁烯)的合成及其在铂和钯催化下的反应。在二乙基氟硅烷存在下，1，2，4，5-四钼苯与镁反应合成了苯并[1，2：4，5]双(1，1，2，2-四乙基-1，2-二硅杂环丁烷-3-烯)(2)。在回流苯中，1与二苯乙炔在(eta^2-ethylene)bis(triphenylphosphine)platinum(O)催化下反应得到1：2-加合物，苯并[1，2：4，5]双(1，1，4，4-四乙基-2，3-二苯基-1，3-二苯基-1，4-四乙基-2，3-二苯基)4-二硅环己-2，5-二烯)，产率为91%。类似的铂(O)催化的1，3-己炔和乙炔在回流苯中的反应，以较高的产率分别得到了相应的1：2-加合物，苯并[1，2：4，5]双(二硅环己二烯)衍生物。在催化量的四(三苯基膦)钯(O)存在下，苯并二(二硅环丁烯)1还与二苯乙炔、3-己炔和乙炔反应，以极高的产率得到相应的1：2加合物。较少

In this paper we report the platinum-catalyzed reactions of isopmpy-substituted benzodisilacyclobutene. The reactions of 3, 4-benzo-1, 1, 2, 2-tetra(isopropy1)-l, 2-disi1acyclobut-3-ene (1) with phenylacetylene and 1-hexyne in the presence of a catalytic amount of (eta^2-ethylene)bis(tripheny1phosphine)platinum(O) at 200ﾟC for 24h gave two types of 1 : 1 ackiucts, 2-phenyl- and 2-butyl-substituted 5, 6-benzo-1 , 1 , 4, 4-tetra(isopropyl)- 1 , 4-disilacyclohexa-2, 5-diene and 2-benzylidene- and 2-pentylidene-substituted 4, 5-benzo- 1, 1 , 3, 3-tetra(isopropyl)-1, 3-disilacyclopent-4ene, respectively. With mesityl- and dimethylphenylsilylacetylene, 1 afforded 2-(mesityl)methylene- and 2-(dimethylphenylsilyl)- methylene4, 5-benzo-1, 1, 3 , 3-tetra(isopmpyl)-1 , 3disilacyclopent-4-ene. Similar reaction of i with trimethylsilyl-acetylene produced an adduict ansing from sp-hybridized C-H bond activation of the acetylene, together with a benzodisilacyclopentene derivative. The reaction of 1 w … More ith dephenylacetylene yielded a 2, 3-diphenyl-5, 6-benzodisilacyclohexa-2, 5-diene derivative, while with methyiphenylacetylene and 2-hexyne, 1 gave 2-benzylidene- and 2-butylidene-5, 6-benzo-1 , 4-cisilacyclohex-5-ene, along with the benzodisilacyclohexa-2, 5-diene deriivatives. Similar treatment of 1 with methyl(trimethylsilyl)acetylene produced a 5, 6-benzo-2-(trimethylsilyl)methylenedisilacyclohexene derivative.We also report the synthesis and platinum- and palladium-catalyzed reactions of benzobis(disilacyclobutene). Benzo[1 , 2 : 4, 5]bis(1, 1 , 2, 2-tetraethyl-1 , 2-disilacyclobut-3-ene) (2) was synthesized by the reaction of1, 2, 4, 5-tetrabmmobenzene with magnesium in the presence of diethyifluorosilane in THF.The reaction of 1 with diphenylacetylene in the presence of a catalytic amount of (eta^2-ethylene)bis(triphenylphosphine)platinum(O) in relluxing benzene gave a 1 : 2-adduct, benzo[1 , 2 : 4, 5]bis(1, 1, 4, 4-tetraethyl -2, 3-diphenyl- 1 , 4-disilacyclohexa-2, 5-diene) in 91% yield. Similar platinum(O)-catalyzed reaction of 1 with 3-hexyne and acetylene in refluxing benzene afforded the respective 1 : 2-adducts, benzo[1 , 2 : 4, 5]bis(disilacyclohexadiene) derivatives in excellent yields. Benzobis(disilacyclobutene) 1 also reacted with diphenylacetylene, 3-hexyne, and acetylene in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(O) to give the corresponding 1 : 2 adducts in excellent yields. Less