Chemical Forums

Chemistry Forums for Students => Organic Chemistry Forum => Organic Spectroscopy => Topic started by: Anagkai on November 13, 2016, 12:48:34 PM

Title: nmr of product (anthranilic acid, isoamyl nitrite and 2-acetoxy-pyridine react)
Post by: Anagkai on November 13, 2016, 12:48:34 PM

I'm supposed to find the product of the reaction of anthranilic acid, isoamyl nitrite and 2-acetoxypyridine. I got an proton nmr spectrum of the product.

That's the spectral data: 2.5 ppm (3H, s), 6.3(1H, td, 6.6/1.2 Hz), 6.6(1H, d, 9.6 Hz), 7.27(1H, dd, 6.6/1.6 Hz), 7.32(1H, dd, 7.2/2.4 Hz), 7.43(1H, dd, 9.6/6.6/2.0 Hz), 7.52(1, td, 8.2/1.6 Hz), 7.62(1, td, 7.2/1.2), 7.73(1, dd, 8.2/1.2)

I thought about that for quite some time, but I didn't find the product.

First part of reation is a diazotation, I think and the anthanilic acid becomes benzyne by elimination of CO₂ and N₂.
Second part I don't really know, I thought about a quinoline derivative, but it doesn't really fit with the number of protons. By the 2.5ppm/3H singulet I can tell that the acetoxy group stays, but otherwise I'm stuck. I have no idea what to make of the coupling constants. I suppose all protons are aromatic (except the 3 mentioned before)
I suppose everything above 6 Hz is ortho coupling, 1.6 / 2 / 2.4 probably meta. 1.2 I'm not sure, it's like between meta and para. I also know there isn't normally meta coupling passing a nitrogen. This could happen here, because there is an N hetero arene and chances are it stays...

Title: Re: nmr of product (anthranilic acid, isoamyl nitrite and 2-acetoxy-pyridine react)
Post by: Vidya on November 22, 2016, 06:51:53 PM

Benzyne and 2-acetoxypyridine can undergo Diels Alder reaction and product so formed can help you in analyzing the NMR data .