Hydroalkoxylation

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Hydroalkoxylation is a chemical reaction that combines alcohols with alkenes or alkynes. The process affords ethers.

The reaction converts alkenes to dialkyl or aryl-alkyl ethers:

R'OH + RCH=CH2 → R'OCH(R)-CH3

Similarly, alkynes are converted to vinyl ethers:

R'OH + RC≡CH → R'OC(R)=CH2

As shown, the reaction follows the Markovnikov rule. The process exhibits good atom-economy in the sense that no byproducts are produced. The reaction is catalyzed by bases and also by transition metal complexes. [1] Usually symmetrical ethers are prepared by dehydration of alcohols and unsymmetrical ethers by the Williamson ether synthesis from alkyl halides and alkali metal alkoxides. [2]

See also

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References

  1. Alonso, F., Beletskaya, I. P., Yus, M., "Transition-Metal-Catalyzed Addition of Heteroatom-Hydrogen Bonds to Alkynes", Chemical Reviews 2004, volume 104, 3079. doi : 10.1021/cr0201068
  2. Wilhelm Heitmann, Günther Strehlke, Dieter Mayer "Ethers, Aliphatic" Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi : 10.1002/14356007.a10_023