makfc - 11-3-2006 at 06:00
I'm trying acetylation of m-HYDROXY BENZALDEHYDE to m-ACETOXY BENZALDEHYDE with acetic anhydride, acetyl chloride & with other possible methods.
Can I get exact route of synthesis, reagents, experimental procedure for this reaction ?
Awaiting your replies...............!!!
MAKFC
(nalini.patel@rediffmail.com)
[Edited on 11-3-2006 by makfc]
Drunkguy - 11-3-2006 at 13:06
Why on earth would u do that? Please explain.
Aldehyde Protection
gsd - 12-3-2006 at 10:34
I think you will have to first protect the aldehyde group. ( may be by using anhydrous AlCl3) and then acetylate the -OH using any of the std.
acetylating agent.
The procedure should be similar to that of preparation of m-phenoxy benzaldehyde for which you should be able to find the references very easily
(especially in the patent literature) as it is an important intermediate for many pastcides.
XxDaTxX - 12-3-2006 at 12:17
"pasticides" ... damn I hate the past too ... but not that much 
Sandmeyer - 12-3-2006 at 12:50
m-Acetoxybenzaldehyde (16). The method of Bender and Nakamura6 was employed. Thus, a 250-mL flask, equipped with a magnetic stirring bar and calcium
sulfate drying tube, was charged with 25.0 g (0.205 mol) of m-hydroxybenzaldehyde and 100 mL of pyridine followed by 25.0 mL of acetic anhydride.
After stirring at room temperature for 40 min, the reaction mixture was diluted with brine and ice and extracted with ethyl acetate (2x). The combined
extracts were washed with 1.2 N aqueous hydrochloric acid (2x), saturated aqueous sodium bicarbonate (2x), and brine, and dried over magnesium
sulfate. Concentration in vacuo gave 32.52 g of a redorange oil which was distilled at reduced pressure to give 24.95 g (74%). of pure 16: bp 100 "C
(1.0 mm). The NMR spectrum showed absorptions at 6 2.25 (s, 3 H), 7.1-7.8 (m, 4 H), 9.78 (s, 1 H).
ref: J. Org. Chem., Vol. 43, No. 11, 1978
Other workers have reported 95% yield using the modified above method (Winkle, Mark R.; Ronald, Robert C.; J. Org. Chem.; 47; 11; 1982; 2101-2108.).
but they provide no further details.
[Edited on 12-3-2006 by Sandmeyer]
acetylation
makfc - 19-3-2006 at 22:10
Thanks Dear !
I'm trying to perform this procedure.
Regards,
MAK