Pinacol-Pinacolone Rearrangement of 1, 2-Di-(p-methoxyphenyl)-ethane-1, 2-diol and Bis-(4-methoxyphenyl)-acetaldehyde in Acid Media

✍ Scribed by Wadie Tadros; Alfy Badie Sakla; Sami Bassili Awad; Abdul-Aziz Amine Helmy

• Publisher: John Wiley and Sons
• Year: 1972
• Tongue: German
• Weight: 338 KB
• Volume: 55
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19720550810

✦ Synopsis

Abstract

1, 2‐Di‐(p‐methoxyphenyl)‐ethane‐1, 2‐diol gave in acid media bis‐(4‐methoxy‐phenyl)‐acetaldehyde, 4‐4′‐dimethoxy‐deoxybenzoin, and 1, 2‐di‐(p‐methoxyphenyl)‐ethylene oxide; their respective yields being influenced by at least 3 factors: (i) the acid, (ii) its concentration, and (iii) the reaction period.

Bis‐(4‐methoxyphenyl)‐acetaldehyde rearranged to the deoxybenzoin in boiling sulfuric (50%) or phosphoric (75%) acids (w/w), and to two isomeric 1, 2‐diacetoxy‐1, 2‐di‐(p‐methoxyphenyl) ethanes when it was heated with acetic anhydride.

The mechanisms of these reactions are discussed.