Reaction #3040

Reaction equation

5-[[3,5-bis(1,1-dimethylethyl) -4-hydroxyphenyl]methylene]-3-[2-(acetyloxy)ethyl]-4-thiazolidinone

5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methylene]-3-[2-(acetyloxy)ethyl]-4-thiazolidinone

ammonium hydroxide

→

desired subtitled intermediate

Yield 46.7%

5-[[3,5-bis(1,1-dimethylethyl) -4-hydroxyphenyl]methylene]-3-(2-hydroxyethyl)-4-thiazolidinone

Yield 46.7%

Solvents

acetonitrile

Conditions

Workup

1. 1
   ConcentrationThe solution was concentrated in vacuo and 500 ml of ethyl acetate
2. 2
   workup.ADDITIONwere added, with the pH
3. 3
   OtherThe layers were separated
4. 4
   Extractionthe aqueous layer extracted with 250 ml of ethyl acetate
5. 5
   WashThe combined organic layers were washed with 250 ml of a saturated sodium chloride solution
6. 6
   Concentrationconcentrated in vacuo
7. 7
   OtherThe residue was crystallized from 95 ml of hexane and 70 ml of ethyl acetate

Procedure

A solution of 85.2 g of 5-[[3,5-bis(1,1-dimethylethyl) -4-hydroxyphenyl]methylene]-3-[2-(acetyloxy)ethyl]-4-thiazolidinone from Example 26 in 1.5 l of acetonitrile was treated with 1 liter of concentrated ammonium hydroxide. The reaction mixture was allowed to stand for approximately 90 hours at room temperature. The solution was concentrated in vacuo and 500 ml of ethyl acetate were added, with the pH adjusted to 3.0 with concentrated hydrochloric acid. The layers were separated and the aqueous layer extracted with 250 ml of ethyl acetate. The combined organic layers were washed with 250 ml of a saturated sodium chloride solution and concentrated in vacuo. The residue was crystallized from 95 ml of hexane and 70 ml of ethyl acetate to provide 35.68 g of the desired subtitled intermediate, m.p. 131°-135° C.

Source