Reduction of Alkynes

Recent Literature

A Pd/C-catalyzed hydrogenation using diphenylsulfide as a catalyst poison selectively reduces olefin and acetylene functionalities without hydrogenolysis of aromatic carbonyls and halogens, benzyl esters, and N-Cbz protective groups.
A. Mori, Y. Miyakawa, E. Ohashi, T. Haga, T. Maegawa, H. Sajiki, Org. Lett., 2006, 8, 3279-3281.

A new recyclable catalyst composed of palladium nanoparticles dispersed in an organic polymer was synthesized by a simple procedure from readily available reagents. This catalyst is robust, and highly active in many organic transformations including alkene and alkyne hydrogenation, carbon-carbon cross-coupling reactions, and aerobic alcohol oxidation.
C. M. Park, M. S. Kwon, J. Park, Synthesis, 2006, 3790-3794.

A generally applicable method for the introduction of gaseous hydrogen into a sealed reaction system under microwave irradiation allows the hydrogenation of various substrates in short reaction times with moderate temperatures between 80 °C and 100 °C with 50 psi of hydrogen.
G. S. Vanier, Synlett, 2007, 131-135.

Treatment of γ-hydroxy-α,β-acetylenic esters with sodium borohydride or Red-Al gave γ-hydroxy-α,β-alkenoic esters by means of trans-selective addition of two hydrogen atoms or a hydrogen atom and an iodine atom across the triple bond.
C. T. Meta, K. Koide, Org. Lett., 2004, 6, 1785-1787.

The hydrosilylation of alkynes using the ruthenium catalyst [Cp*Ru(MeCN)₃]PF₆ gives only (Z)-trans addition products. Subsequent protodesilylation of the crude vinylsilane products by the action of cuprous iodide and TBAF provides a general trans-alkyne reduction, which is compatible with many sensitive functional groups.
B. M. Trost, Z. T. Ball, T. Joege, J. Am. Chem. Soc., 2002, 124, 7922-7923.

Indium hydride generated from readily available Et₃SiH and InCl₃ offers mild conditions and low toxicity, and is therefore a promising alternative to Bu₃SnH.
N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6, 4981-4983.

N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6, 4981-4983.

A stereoselective synthesis of (Z)-β-bromo Baylis-Hillman ketones has been achieved using a one-pot three-component reaction. The new system uses MgBr₂ as both the Lewis acidic promoter and the bromine source.
H.-X. Wei, R. L. Jasoni, J. Hu, G. Li, P. W. Pare, Tetrahedron, 2004, 60, 10233-10237.