3-formylbut-2-enyl acetate

Vitamin A intermediated C5,namely 3- formylbut- 2- enyl acetate,which was used C15 + C5 synthesis route of vitamin A. 2- Chloro- 1- ethanol was used as starting material,esterified by acetic anhydride and protected by phosphate ester,and then reacted with 1,1- dimethoxy- 2propanone,trans- γ- acetoxytiglic aldehyde dimethyl acetal can be obtained,subsequently deprotection and 3- formylbut- 2- enyl acetate can be achieved. 

3-Formylcrotyl Acetate can be used as a vitamin A intermediate.