Preparation by Friedel–Crafts acylation of resorcinol,
? with acetic anhydride,
– in the presence of zinc chloride
at 142–150° for 15 min (96%) or at 150–160° for 20 min (68%)
; – in the presence of ferric chloride
. – in the presence of concentrated sulfuric acid at 130° for 15 min (15%)
; – in the presence of 70% perchloric acid at 125–135° for 15–20 min (42%)
. ? with acetyl chloride,
– in the presence of zinc chloride, at 120°
; – in the presence of ferric chloride, at 150° for 15 min (60%) or at reflux for 30 min
; – in the presence of concentrated sulfuric acid (18%)
. ? by a typical Friedel–Crafts reaction (24%).
1,1′-(4,6-Dihydroxy-1,3-phenylene)bisethanone (4,6-diacetylresorcinol, DAR) is a bifunctional carbonyl compound. Its synthesis by acetylating resorcinol in the presence of zinc chloride has been reported. The crystal structure of DAR has been studied.