Skip to main content
Chemistry LibreTexts

Hydroboration-Oxidation

  1. Last updated
  2. Save as PDF
  • Page ID
    40474

    • \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

    Alkenes do not undergo hydration upon treatment with water even at very high temperatures. There are two approaches to hydrating alkenes:

    1. Reaction of the alkene with water in the presence of a strong-acid catalyst.
    2. Using an indirect method

    Hydroboration-oxidation, sometimes casually called hydroboration for convenience, is a common indirect method used to hydrate alkenes.

    hydroborationoxidaiton1.png

    net reaction:

    hydroborationoxidaiton2.png

    The protocol is carried out in two stages:

    Stage 1: Hydroboration

    The alkene is treated with a source of borane ( diborane or borane-THF complex), which converts the alkene into a trialkylborane.

    Stage 2: Oxidation

    The trialkylborane is treated with H2O2 and a strong base, usually NaOH, in aqueous medium, which converts the trialkylborane into an alcohol.

    eg:
    Stage 1:

    hydroborationoxidation3.png

    This reaction is an anti-Markovnikov addition and a syn addition.

    Stage 2:

    hydroborationoxidation4.png

    Stage 1 + Stage 2 =

    hydroborationoxidation5.png

    The net reaction is an anti-Markovnikov addition:

    hydroborationoxidation6.png

    see also oxymercuration-reduction

    This page titled Hydroboration-Oxidation is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Gamini Gunawardena via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

    1. Back to top
    • Was this article helpful?

    Recommended articles

    1. Article type
      Section or Page
      Author
      Gamini Gunawardena
      License
      All Rights Reserved
      Show Page TOC
      no on page
    2. Tags
      1. source@http://www.ochempal.org