Electrochemical Deprotection ofpara-Methoxybenzyl Ethers in a Flow Electrolysis Cell

• DOI: 10.1021/acs.orglett.7b00641
• Publication Date: 2017-04-05T07:58:34Z
• Authors: Robert A. Green; Katherine E. Jolley; Azzam A. M. Al-Ha...; Derek Pletcher; David C. Harrowven; Oscar De Frutos; Carlos Mateos; David J. Klauber; Juan A. Rincón; Richard C. D. Brown
• Keywords: 01 natural sciences; 0104 chemical sciences

Electrochemical deprotection of p-methoxybenzyl (PMB) ethers was performed in an undivided electrochemical flow reactor in MeOH solution, leading to the unmasked alcohol and p-methoxybenzaldehyde dimethyl acetal as a byproduct. The electrochemical method removes the need for chemical oxidants, and added electrolyte (BF4NEt4) can be recovered and reused. The method was applied to 17 substrates with high conversions in a single pass, yields up to 92%, and up to 7.5 g h-1 productivity. The PMB protecting group was also selectively removed in the presence of some other common alcohol protecting groups.