Question

Explain the following reaction questions on an analysis to the experimental procedure of borohydride reduction of a ketone.

What happens if an excess of reducing agent is used?

The reaction solvent is methanol?

The reaction is initially carried out at less than 20C then raised to 50C.

4. upon work-up, brine is added to the reaction mix and the ethereal solution is then washed with water and brine?

Answer 1

Explain the following reaction questions on an analysis to the experimental procedure of borohydride reduction of a ketone.

What happens if an excess of reducing agent is used?

     Generally, a little excess of NaBH4 is used to complete the reduction and there is no side effect for this.

The reaction solvent is methanol?

     This reaction is better done in alcoholic solution due its better solubility.

The reaction is initially carried out at less than 20C then raised to 50C.

     Depending on the substrate, heating is required. If the reaction does not move below 20C then the temperature needs to be raised until it moves,

4. upon work-up, brine is added to the reaction mix and the ethereal solution is then washed with water and brine?

     Brine is the saturated solution of NaCl in water. It helps in portioning of the reaction mixture in to organic and aqueous phases. Finally to remove trace of water might be present in ethereal solution it was washed brine which makes the solution clearer.