Syringaldehyde 35dimethoxy4hydroxybenzaldehyde [7
5-bromovanillirie (5mmol) is refluxed with EtOAc (3mmol) and CuBr (immol) in 5 M NaOMe/MeOH (10 ml) for 14 hours. Classical work-up (addition of water and acidification followed by extraction of the phenol) leads to pure syringaldehyde (95%). When starting from the more soluble 5-bromovanilline dimethyl acetal, reaction is achieved within 2 hours (yield 98%). Preparation of this acetal is probably not worth the extra work. Substituting EtONa for MeONa seems to work, too, producing 2-ethoxy-3-OH-4-methoxybenzaldehyde, useful for ethoxy-derivatives of Mescaline.
The above synthesis, although performed on a small scale, is easily scaled up to industrial size (French Pat. 2,669,922, CA 118; P6734u). It is a general procedure for substituting aryl-Br with -OMe or -OEt, giving us the possibility to produce other compounds from already known substances, e.g bromination of MDA yields 6-Br-MDA. This is converted by the above procedure to MMDA-2, #133, active at 25-50mg, 8-12 hrs.
Asaronealdehyde (2,4,5-trimethoxy-benzaldehyde) can be produced in the following way: Methylate resorcinol. Product is 1,3-di-MeO-benzene. Do a Vilsmeyer aldehyde synthesis with poci3/N-methylformanilide to obtain 2,4-di-MeO-benzaldehyde. Brominate and treat as described above to obtain asaronaldehyde.
Syringaldehyde is easily methylated or ethylated with the known procedures in high yields forming the highly-desirable 3,4,5-trimethoxybenzaldehyde or the 3,5-di-MeO-4-EtO-benzaldehyde (Escaline, #72, 40-60 mg, 8-12 hrs.).
Continue reading here: Trimethoxybenzaldehyde [3 from 5hydroxyvanillin
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