Lewis Acid/Base Interaction Matrix Database


Type 13 Lewis Acid/Base Complexation Chemistry
Reduction of Lewis Acid

Bonding:

s-HOMO Lewis bases are reducing agents, so complexation with hydride or hydrogen is also classed as reduction.

However, with respect to carbenium ions and organic chemistry, as C-H bonds are polarised Cδ––Hδ+, ie as weak Brønsted acids, Type 13 complexes reverse their C-H bond polarisation:

          C+ +   H       C–H        Cδ––Hδ+

and so become Type 3 complexes.

Charge: Complexes may be negatively charged or they may be neutral, or a reaction may occur.
Chemistry:

Carbenium ion (ie where the Lewis acid = R3C+ + hydride ion) complexation reactions are rare as both species interact strongly with their counter ions.

  • The true X + Y X-Y complexation reaction would have to be performed under high vacuum vapor phase conditions with the reactive species generated by an experimentally exotic process such as laser induced dissociation.
  • Alkyl halides, such as 3-bromohexane, are readily reduced by H2 plus a catalyst, or by hydride ion donor reagents, as are carbonyl functions.
  • Proton abstraction may occur if there is an acidic proton present and a strongly basic hydride donor reagent is used.
  • A few C-H functions can act donors of hydride ion: aldehydes in the Cannizzaro reaction and isopropoxide ions during Meerwein-Ponndorf-Varley reduction.
Congeneric Series: Few series.
Type 13 Lewis acid/base complex (generic)
Acetaldehyde

more here
Aldehyde (generic)

more here
1° Alkoxide ion (generic)

more here
Alkoxy aluminium hydride ion (generic)

more here
Alkoxy borohydride ion (generic)

more here
Alkyl aluminium hydride ion (generic)

more here
Alkyl borohydride ion (generic)

more here
Alkyl, -CH2- (generic)

more here
Dialkoxyaluminium hydride ion (generic)

more here
Dialkoxyborohydride ion (generic)

more here
Dialkylaluminium hydride ion (generic)

more here
Dialkylborohydride ion (generic)

more here
Diborane

more here
Diisobutylaluminium hydride

more here
Ethoxide ion

more here
Hydrogen bromide

more here
Hydrogen chloride

more here
Hydrogen iodide

more here
Isopropyl alkoxide ion

more here
Methoxide ion

more here
Tetrahydroaluminate

more here
Tetrahydroborate ion

more here
Trialkoxyaluminium hydride ion (generic)

more here
Trialkoxyborohydride ion (generic)

more here
Trialkylaluminium hydride ion (generic)

more here
Trialkylborohydride ion (generic)

more here


Interactions and reactions classified as:
Type 13 Lewis Acid/Base Complexation Chemistry
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1
      1 +3 1
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1
       +
      1 +1 1
      1 +1 1
      1 +1 1
      1 +1 1



Poster
Nucleophiles & Bases

© Mark R. Leach 1999-


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