How do you prepare anhydrous methanolic formaldehyde? With dimethoxymethane or paraformaldehyde?

No, I just want an anhydrous solution of formaldehyde (HCHO) in methanol. The commercial solution are roughly 40% formaldehyde, 15% methanol and 55% water, therefore I thought it would be better to start with a form of formaldehyde which is anhydrous from the beginning, like paraformaldehyde (its dehydrated polymer) or dimethoxymethane (CH3-O-CH2-O-CH3, its dimethyl acetal).

He means an anhydrous solution of formaldehyde (HCHO) in methanol (CH3OH) as solvent.

Dimethoxymethane is an acetal, which are unstable and would depolymerize (with water) to methanol and formaldehyde. I would not recommend this route as it needs water and you want an anhydrous system.

This problem is really tricky. As bad as it sounds........maybe gassing warm methanol with formaldehyde gas?

[EDIT]See what happens when you go answer the phone in the middle of a post?    Rhodium beat me to it.[/EDIT]

PrimoPyro

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Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

40% formaldehyde, 15% methanol and 55% water

damn chief, your supplier is hooking you up with 110% of what you're paying for.

Heating paraformaldehyde until it forms formaldehyde and gassing this into methanol would probably be the best way to go.  Make sure to put an inline trap in, as the apparatus will suck back like mad when you stop applying heat.

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All paths are the same: they lead nowhere

Hey Chief,

Just so you know, anhydrous 10% formaldehyde in methanol is a common reagent in any microbiology/tissue culture lab so I'm sure you can get it from Sigma very easily(and cheaply too).