Alpha-Ketoisovaleric acid
# Alpha-Ketoisovaleric acid

α-Ketoisovaleric acid is an organic compound with the formula $(CH_3)_2CHC(O)CO_2H.$ It is a ketoacid. With a melting point just above room temperature, it is usually an oil or semi-solid. The compound is colorless. It is a metabolite of valine and a precursor to pantothenic acid, a prosthetic group found in several cofactors. In the biological context, is usually encountered as its conjugate base ketoisovalerate, $(CH_3)_2CHC(O)CO_2^−.$

## Synthesis and reactions

α-Ketoisovalerate undergoes hydroxymethylation to give ketopantoate:

    $(CH_3)_2CHC(O)CO_2^−$ + $CH_2O$ → $HOCH_2(CH_3)_2CC(O)CO_2^−$

This conversion is catalyzed by ketopantoate hydroxymethyltransferase.

Like many α-ketoacids, α-ketoisovaleric acid is prone to decarboxylation to give isobutyraldehyde:

    $(CH_3)_2CHC(O)CO_2H$ → $(CH_3)_2CHCHO$ + $CO_2$

Genetic engineering has been used to produce the biofuel isobutanol by reduction of isobutyraldehyde obtained from ketoisovalerate.

