Prins Cyclization of Styrenes or Acetophenone Catalyzed by DBSA in Water

Abstract

Dodecylbenzenesulfonic acid (DBSA) was proved to be an efficient catalyst for Prins cyclization of styrenes and formaldehyde or acetaldehyde in water. A tandem dehydration/Prins cyclization reaction using a tertiary alcohol and formaldehyde as substrates proceeded very well by using DBSA as catalyst. Acetophenone, which is less reactive compared with styrene, can also react with formaldehyde when catalyzed by DBSA in water to afford 1,3-dioxan-5-ylphenylmethanone in good yield.

GRAPHICAL ABSTRACT

Keywords:

• DBSA
• 1,3-dioxane
• organic reactions in water
• Prins cyclization

ACKNOWLEDGMENT

We gratefully acknowledge the financial support from the Doctoral Research Fund of Henan University of Traditional Chinese Medicine.

Notes

^a Styrene: 1.0 mmol.

^b Formaldehyde was used in 2.5 equiv.

^c 0.5 ml of water was added.

^d Reaction was conducted on a 10-mmol scale.

^a Styrene: 1.0 mmol, formaldehyde aqueous solution: 4.0 mmol, DBSA: 12 mol%, temperature: 80 °C.

^b DBSA: 20 mol% and temperature: 90%.

^c Temperature: 50 °C.