Question

Convert CH3CHO to CCl3CHO
​I mean , will beCl2 and light enough?

Answer 1

No, Cl2 and light is not enough for the conversion of CH3CHO (ethanal) to Cl3CCHO (chloral).

• Chloral is commercially synthesized from ethanal with the help of chlorine and water, in the presence of antimony chloride, used as a catalyst, by rising the temperautre from 0°C to 90°C. A mixture of chloral hydrate and hydrocholric acid is formed, from which chloral hydrate is obtained by distillation, followed by dehydration with sulphuric acid to obtain chloral.

• CH3CHO + 3Cl2 + H2O + ∆ + SbCl3  → Cl3CCH(OH)2 + 3HCl

• The chloral hydrate formed is obtained by distillation, and then reacted with concentrated sulphuric acid to separate it into chloral and water. The chloral is finally obtained by distillation.

Cl3CCH(OH)2 + conc. H2SO4  → Cl3CCHO + H2O