Compound 4b
(1S,2R,3R,4S,E)-3-benzoyl-6-benzylidene-1'-methylspiro[bicyclo[2.2.1]heptane-2,3'-pyrrolo[2,3-b]pyridine]-2',5(1'H)-dione
From: Switchable regioselectivity in amine-catalysed asymmetric cycloadditions
View in PubChem | 1H NMR | 13C NMR | HPLC mixture | HPLC | MDL Molfile | ChemDraw
Compound data: CIF
Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.
The title compound was prepared according to the general procedure for switchable regio- and chemoselective [4 + 2] cycloaddition as outlined in the synthesis of 4a. 4b, white solid, 37.2 mg, 86% yield; [α]D20 = 24.5 (c = 0.70 in CHCl3); 99% e.e., determined by HPLC analysis [Daicel chiralpak AD, n-hexane/i-PrOH = 80/20, 1.0 mL/min, λ = 254 nm, t (major) = 29.07 min, t (minor) = 21.39 min]; 1H NMR (400 MHz, CDCl3): δ (ppm) 8.00 (dd, J = 5.2 Hz, 1.6 Hz, 1H), 7.54 (s, 1H), 7.40-7.33 (m, 4H), 7.30-7.29 (m, 3H), 7.22-7.17 (m, 4H), 6.81 (dd, J = 7.2 Hz, 4.8 Hz, 1H), 4.25 (m, 1H), 3.50 (m, 1H), 3.45 (m, 1H), 3.18 (s, 3H), 2.82 (m, 1H), 2.11 (m, 1H); 13C NMR (100 MHz, CDCl3): δ (ppm) 203.3, 196.6, 175.1, 147.2, 136.4, 136.0, 134.5, 133.5, 132.2, 131.6, 129.7, 129.4, 128.7, 128.4, 127.6, 123.7, 118.0, 56.8, 53.3, 52.9, 50.5, 37.7, 25.5; ESI-HRMS: calcd. for C28H22N2O3+Na+ 457.1523, found 457.1522.
