• 10.1021/ja0121033
  • Journal of the American Chemical Society
  • Volume 123
  • December 2001
  • pp 12726-12727

trans-hydrosilylation internal alkynes: notes/modifications



Trost and Ball discovered the efficient Ru-catalyst for Markovnikov hydrosilylation of terminal alkynes as well as trans-hydrosilylation of internal alkynes. This reaction is the only general method for accessing geminal alkenylsilanes via hydrosilylation of terminal alkynes. In addition, this is the most general trans-hydrosilylation of internal alkynes giving access to (Z)-vinylasilanes. The reaction features high yields and selectivity, broad substrate scope and good functional group compatibility. The origin of selectivity and the reaction mechanism were disclosed in following publications.

The Reaction of Interest:

I was particularly interested in trans-hydrosilylation of internal alkynes with HSi(OEt)3. In this manuscript, the authors reported that hydrosilylation of 4-octane with HSi(OEt)3 afforded the product in 99% yield (Table 2, Entry a).

According to the described procedure, hydrosilylation of 3-hexyne with both HSi(OEt)3 and HSi(OMe)3 furnished the corresponding (Z)-vinylsilanes in almost quantitative yields and perfect stereoselectivity (GC-MS and NMR analysis). 

Practical Observations:

- Excellent yield and stereoselectivity.

- The reaction robust and not sensitive to traces of air/moisture.


- The order of addition of reagents and catalyst does not influence the reaction efficiency. 

- The reaction can be performed in a Wheaton V-vial or a round-bottom flask under an inert atmpsphere.

- The reaction is scalable (up to 10 mmol).

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