How to Face an Organic Reaction Involving a Reducing Agent – Part 1

Both Lithium aluminum hydride, LiAlH4 or Li[AlH4] (LAH) and Sodium borohydride (aka Sodium tetrahydridoborate or Sodium tetrahydroborate), NaBH4 or Na[BH4] are inorganic compounds, the former being a stronger reducing agent.


If the product has a new chiral center, stereoisomers may be obtained.

Question:

Predict the major products of the following reactions:



Click/tap to enlarge the image

Solution infographic:



Click/tap to enlarge the image


Substrate

Products by

 

NaBH4

LAH

Aldehydes

10 alcohols

10 alcohols

Ketones

20 alcohols

20 alcohols

Esters

No rxn

10 alcohols

Carboxylic acids

No rxn

10 alcohols

Acid halides

10 alcohols

10 alcohols

Acid anhydrides

10 alcohols

10 alcohols

Amides

No rxn

Amines

Nitriles

No rxn

10 amines

Alkyl halides

No rxn

Alkanes

Epoxides

No rxn

Alcohols

Cinnamic groups

No rxn

Saturated 10 alcohols

The nature of reduction may change depending on the stoichiometric use and/or elevated temperature and/or use of another reagent like a catalyst.

Have you now felt a reduction in confusion about the above reducing agents❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

NOTE: Updated since published

References:

(1)    Lithium aluminium hydride. Wikipedia. https://en.wikipedia.org/wiki/Lithium_aluminium_hydride.

(2)    Sodium borohydride. Wikipedia. https://en.wikipedia.org/wiki/Sodium_borohydride.

(3)    Chouhan, M. S. Advanced Problems in Organic Chemistry for JEE, 11th Ed.

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