TiCl4, Dioxane—A Facile and Efficient System for De-O-Benzylation, De-O-Allylation, and De-O-Xylylation of Phenolic Ethers

Simultaneous de-O-xylylation and reductive coupling was observed when 1 equiv. of the dialdehyde 2a/2b was treated with 5 equiv. of each TiCl4 and Zinc which lead to the development of TiCl4 in dioxane as a new system for the facile deprotection of phenolic ethers 4a–4d, 5a–5d, and 6a–6c.