|Esterification of Vanillin with an Acid
||[Mar. 25th, 2009|04:17 pm]
I am performing a reaction with vanillin, acetic anhydride, and sulfuric acid. An acylation does NOT occur, because although it can happen with a base, an acid yields a different product.
Literature value for the melting point is 90 - 91 degrees celsius.
An IR spectra taken shows peaks at 1609, 1711, 1765, 2850 (moderate peak), 2920, and a 3388 stretch. 1609 indicates an aromatic ring; 1711 is C=O, 1765 indicates a carboxylic ester, right? I am a bit confused about that. 2850 is probably an sp3 hybridized hydrogen, as is the 2920 stretch; and the 3388 stretch, I believe, is an OH stretch.
The NMR is of the following: there are 5 peaks (5 different kinds of hydrogens). A peak at 2.2, 2.4, 3.8, 7.2, and 7.6. The heights (which indicate proportionality) are 8.658, 3, 3, 2.9, and 1, respectively. 2.2 & 2.4 are very close to each other and are indicative of hydrogens on a methyl group attached to a benzene. The 3.8 peak seems like a hydrogen attached to a methyl group carbon that possesses an OH substituent. 7.2 is the benzene ring, and 7.6 is probably a hydrogen that is part of an OH group that is directly attached to the benzene ring.
NMRs have always troubled me, and the peaks are not as clean as the problems we are assigned... Along with the proportionalities presented, I'm just confused.
Any help would be GREATLY appreciated. :)