Ruthenium Catalyzed Dimerization of Trimethysilylacetylene to 1,4-Bis(trimethylsilyl)butatriene and Its Isomerization to (Z)-1,4-Bis(trimethylsilyl)-1-buten-3-yne
rhodium-(Z)-butatriene complexes 3. The butatrienes coordinated to Rh with the central double bond in an η2-fashion. (Z)-Butatrienes on 3 isomerized to (E)-form at 70 °C to afford (E)-butatriene complexes 4 with excellent E/Z ratios (E/Z = 97/3–99/1). The molecular structure of 4b (R = SiMe3, Ar = p-tolyl) was determined by X-ray diffraction analysis. Hydrosilation of 1 was catalyzed by rhodiumcomplexes to give
1,4-二取代丁三烯,(Z)-R-CH=C=C=CH-R (1, R = SiMe3, t-Bu),与 RhCl(PAr3)3 (Ar = Ph, p-tolyl ) 得到铑-(Z)-丁三烯配合物 3. 丁三烯以 η2 方式与中心双键配位到 Rh。3 上的 (Z)-丁三烯在 70 °C 下异构化为 (E)-形式,以提供具有优异 E/Z 比 (E/Z = 97/3–99/1) 的 (E)-丁三烯配合物 4。4b (R = SiMe3, Ar = p-tolyl) 的分子结构通过 X 射线衍射分析确定。1 的氢化硅烷由铑配合物催化得到丙二烯作为主要产物,伴随着 1,3-二烯作为次要产物,这是硅烷的 2,1-加成和 2,3-反加成的结果。
Ruthenium Catalyzed Dimerization of Trimethysilylacetylene to 1,4-Bis(trimethylsilyl)butatriene and Its Isomerization to (<i>Z</i>)-1,4-Bis(trimethylsilyl)-1-buten-3-yne
作者:Yasuo Wakatsuki、Hiroshi Yamazaki、Nami Kumegawa、Perminder S. Johar
DOI:10.1246/bcsj.66.987
日期:1993.3
Trimethylsilylacetylene was catalytically dimerized by Ru(cod)(cot)/PR3 (cod = 1,5-cyclooctadiene, cot = cyclooctatriene) to give either Me3SiCH=C=C=CHSiMe3 when PR3 = PPh3 or (Z)-Me3SiCH=CH–C≡CSiMe3 when PR3 = PBun3, the latter being formed by stereoselective isomerization of initially formed (Z)-Me3SiCH=C=C=CHSiMe3.