Categories: C-C Bond Formation > Chains > Alkynes >

Synthesis of substituted 1,3-enynes

Related:

Name Reactions

Recent Literature

The cross-coupling reaction of (E)- and (Z)-alk-1-enyldialkylborane with (trimethylsilyl)ethynyl bromide proceeds in the presence of a catalytic amount of copper(II) acetylacetonate and a base under extremely mild conditions to provide conjugated enynes with a distal carbon-carbon triple bond.
M. Hoshi, N. Kawamura, K. Shirakawa, Synthesis, 2006, 1961-1970.

Cross-coupling of 1-alkynes with vinyl iodides catalyzed by CuI/N,N-dimethylglycine affords conjugated enynes in good to excellent yields. Heating a mixture of 2-bromotrifluoroacetanilide, 1-alkyne in the presence of CuI/L-proline leads to the formation of the corresponding indole.
F. Liu, D. Ma, J. Org. Chem., 2007, 72, 4844-4850.

A copper(I)-catalyzed coupling of alkynes with vinyl iodides affords various enynes in good to excellent yields, tolerates a variety of functional groups, and does not require the use of expensive additives.
C. G. Bates, P. Saejueng, D. Venkataraman, Org. Lett., 2004, 6, 1441-1444.

Multifunctional palladium catalysis allows a one-pot stereocontrolled synthesis of tetrasubstituted methyl ketones and enynes. The homogeneous palladium dihalide catalyst is used for the bromo-/chloroallylation of alkynes and in situ for subsequent Wacker-Tsuji oxidation or Sonogashira cross-coupling.
A. N. Thadani, V. H. Rawal, Org. Lett., 2002, 4, 4321-4323.

An efficient, palladium-catalyzed synthesis of 2-alkene-4-ynoates and -nitriles by a simple reaction of vic-diiodo-(E)-alkenes with acrylic esters and nitriles in water leads to (E)-isomers from acrylic esters exclusively, whereas (Z)-isomers are obtained in high stereoselectivity from reactions of acrylonitrile. The in situ prepared Pd(0) nanoparticles can be recycled.
B. C. Ranu, K. Chattopadhyay, Org. Lett., 2007, 9, 2409-2412.

B. C. Ranu, K. Chattopadhyay, Org. Lett., 2007, 9, 2409-2412.

A straightforward one-pot approach to highly diverse conjugated enynes, starting from carbonyl precursors has been developed. The low nucleophilic phosphazene bases, which are used for the generation of the alkenyl nonaflates and the terminal alkynes, are compatible with NfF and do not impede the subsequent Sonogashira reaction.
I. M. Lyapkalo, M. A. K. Vogel, Angew. Chem. Int. Ed., 2006, 45, 4019-4023.

2-Alkynyl esters are stereo- and regioselectively converted to E-β-chloro-α-iodo-α,β-unsaturated esters by exposure to Bu₄NI in refluxing dichloroethane. Single-isomer tetrasubstituted olefins bearing four different carbon substituents are then synthesized by sequential palladium-catalyzed coupling reactions.
A. B. Lemay, K. S. Vulic, W. W. Ogilvie, J. Org. Chem., 2006, 71, 3615-3618.

Alkynylboration of alkynes with alkynyl(pinacol)boranes in the presence of nickel catalysts gave cis-1-borylbut-1-en-3-yne derivatives. Some boryl-substituted enynes were reacted with sp² halides under Suzuki-Miyaura coupling conditions.
M. Suginome, M. Shirakura, A. Yamamoto, J. Am. Chem. Soc., 2006, 128, 14438-14439.