2-Hydroxy-1,3-bis(7,7,8,9,9-pentamethyl-2,4-dioxo-1,3,8-triazaspiro[4.5]dec-3-yl)propane → 2-Acetoxy-1,3-bis(1-acetyl-7,7,8,9,9-pentamethyl2,4-dioxo-1,3,8-triazaspiro[4.5]dec-3-yl)propane

Participants

Reaction Steps

A solution of 5.3 g of 2-hydroxy-1,3-bis(7,7,8,9,9-pentamethyl2,4-dioxo-1,3,8-triazaspiro[4.5]dec-3-yl)propane (prepared as described in Example 22) in 70 ml of acetic anhydride was heated, with stirring, at 120°-130° C. for 8 hours. The reaction mixture was then condensed by evaporation under reduced pressure and the residue was dissolved in 200 ml of benzene. The benzene solution was washed successively with a 3% w/w aqueous solution of sodium carbonate and water and then dried over anhydrous potassium carbonate. The solvent was removed from the solution to give crystals, which were recrystallised from benzene. The desired Compound No. 194 was obtained in the form of white crystals, melting at 105°-108° C.

Provenance & Evidence