Cleavage of benzyl ethers by triphenylphosphine hydrobromide

✍ Scribed by Mani Ramanathan; Duen-Ren Hou

• Book ID: 104098346
• Publisher: Elsevier Science
• Year: 2010
• Tongue: French
• Weight: 802 KB
• Volume: 51
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2010.09.065

✦ Synopsis

Triphenylphosphine hydrobromide was found to cleave the benzyl ethers derived from 1°, 2°alkyl, and aryl alcohols to the corresponding alcohols and benzyltriphenylphosphonium bromide in good yields. Alkene and allyl phosphonium salts were produced from the benzyl ethers with 3°alkyl and allyl groups, respectively. These results indicate that the formation of the product is determined by the relative stability of the carbocationic intermediate. The anhydrous, stoichiometric amount of PPh 3 ÁHBr offers a new and effective method for the deprotection of benzyl ethers.