Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Preparation of Crude 2-Hydroxy-5-Methoxybenzaldehyde. Methanol?
Cookie Monster
Harmless
*




Posts: 3
Registered: 7-6-2021
Member Is Offline


biggrin.gif posted on 11-6-2021 at 12:50
Preparation of Crude 2-Hydroxy-5-Methoxybenzaldehyde. Methanol?


Hi, this about patent
https://patents.google.com/patent/US6670510B2/en
“ Example 1 Preparation of Crude 2-Hydroxy-5-Methoxybenzaldehyde.
A mixture of 600 g of acetonitrile, 186.2 g of 4-methoxyphenol (1.5 moles) and 214 g (2.25 moles) of anhydrous magnesium chloride was warmed to 45° C. and 227.4 g (2.25 moles) of triethylamine was added dropwise at that temperature. Paraformaldehyde (150 g, 4.75 moles) was then added and the reaction was heated to reflux. Methanol was removed over 3 hours by distillation, using a 10-inch column packed with Penn-State packing. “

Where does methanol come from? Of the reaction? Forgot to add it at the beginning?

De donde sale el metanol? De la reacción? Se han olvidado añadirlo al principio?.

Thanks
Joaquin
Spain
View user's profile View All Posts By User
karlos³
International Hazard
*****




Posts: 1520
Registered: 10-1-2011
Location: yes!
Member Is Offline

Mood: oxazolidinic 8)

[*] posted on 11-6-2021 at 12:56


Reduction of the formaldehyde, I suppose.
View user's profile View All Posts By User
Amos
International Hazard
*****




Posts: 1406
Registered: 25-3-2014
Location: Yes
Member Is Offline

Mood: No

[*] posted on 11-6-2021 at 13:57


This looks like a similar reaction to the Casiraghi formylation, whose mechanism and scope are detailed here:
https://sci-hub.se/10.1039/P19800001862

If that link doesn't work directly, the paper is Selective reactions between phenols and formaldehyde. A novel route to salicylaldehydes. Journal of the Chemical Society, Perkin Transactions 1, 1862. doi:10.1039/p19800001862
View user's profile View All Posts By User

  Go To Top