Question

Identify products peaks A-D in Diels-Alder reaction where we used Anthracene and Maleic anhydride to produce Diels-Alder Product

7.41 7.40 7.26 odds 7.34 1-7.34 7.33 1.7.22 7.21 -7.21 17.20 17.20 17.18 6621 17.39 SE2 44.83 14.83 SRB 3.60 3.58 3.56 3.50 3.48 3.46 C (dd) 7.45 7.40 735 3.54 3.52 11 (ppm) 730 725 11 ppm) 720 7.15 7.10 B (da) A (dt) 7.397.20 E dd) 3.53 1.98 1,93 4.00 2.01 6.6 6.4 6.2 6.0 5.8 5.6 5.4 5.2 5.0 48 4.6 4.4 4.2 4.0 3.8 3.6 3.4 3. 1.8 7.6 7.4 7.2 7.0 6.8 diels-alder-product_PROTON_02 -70% yield

Answer 1

D Е A А в Е E: 3.53ppm, 2H (dd): The most upfield alkyl protons, they have only one direct coupling partner, however signal is dd hence it must be due to long range coupling D: 4.83ppm, 2H(t): the B-protons hence down field alkyl protons. Has two coupling partners. A: 7.20ppm, 4H(dt): aromatic protons has ortho as well as meta coupling partners B: 7.34ppm, 2H(dd): from the ring which is close to anhydride ring has anisotropic effect C: 7.39ppm, 2H(dd): from the ring which is away from the anhydride ring and has ortho as well as meta coupling. No anisotropic effect.