Sakurai Addition and Ring Annulation of Allylsilanes with α,β-Unsaturated Esters. Experimental Results and ab Initio Theoretical Predictions Examining Allylsilane Reactivity
作者:Michael G. Organ、Vladimir Dragan、Michael Miller、Robert D. J. Froese、John D. Goddard
DOI:10.1021/jo991177i
日期:2000.6.1
hyperconjugative stabilization can occur on the basis of the bond lengths and angles necessary to promote good orbital overlap between the Si-Calpha bond and the empty p orbital on Cbeta. However, the gas-phase reaction of the triisopropylallylsilane with acrolein and methyl acrylate led to comparatively low energy barriers of 13.1 and 24.5, respectively, which is consistent with its high experimental
Five-membered ring annulation via propargyl- and allylsilanes
作者:Rick L. Danheiser、Brian R. Dixon、Robert W. Gleason
DOI:10.1021/jo00049a006
日期:1992.11
Allyl- and propargylsilanes can serve as three-carbon components in a [3 + 2] annulation strategy for the synthesis of five-membered carbocycles and heterocycles.
[3+2] cydoadditions of allylsilanes, Part 3. diastereoselective construction of two contiguous quaternary carbon centers by [3+2] cycloaddition of allyltrisisopropylsilane
作者:Hans-Joachim Knölker、Regina Graf
DOI:10.1016/s0040-4039(00)74083-4
日期:1993.7
A diastereoselective synthesis of 1,2-annulated and spiroannulated bicyclic ring systems with concomitant generation of two contiguous quaternary carbon atoms is achieved by [3+2] cycloaddition of allyltrisisopropylsilane to the appropriate enones.
Cyclobutane ring formation by triflic imide catalyzed [2+2]-cycloaddition of allylsilanes
Cyclobutane forming [2+2]-cycloaddition reactions of allylsilane with electron-deficient olefin is promoted by triflic imide (Tf2NH). Triflic imide is converted in situ to silyl triflic imide (R3SNTf2), which serves as the actual catalyst for this process. When these reactions take place at higher than ambient temperatures, thermodynamically more stable anti-cyclobutanes are generated preferentially by equilibration of the initially formed adducts via retro [2+2]-cycloaddition. (c) 2006 Elsevier Ltd. All rights reserved.