Answers are grounded in this paper and cite their sources.
Synthesis of 3,4-dimethoxy-5-hydroxybenzaldehyde (1) in three steps from vanillin with the key step being a copper catalyzed hydrolysis of 5-bromovanillin to give 4,5-dihydroxy-3-methoxybenzaldehyde.
No takes yet. Share an insight, caveat, or question.
Ellis et al. (1998) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: