With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.872-32-2,2-Methyl-1-pyrroline,as a common compound, the synthetic route is as follows.
n-Butyllithium (53.0 mL, 133 mmol, 2.5 M solution in hexanes) was added dropwise to a stirred solution of diisopropylamine (18.6 mL, 133 mmol) in THF (120 mL) at 0 C. After 5 min, the solution was cooled to -78 C and a solution of 2-methyl-1-pyrroline (11.4 mL, 120 mmol) in THF (120 mL) was added dropwise. The reaction mixture was stirred at -78 C for 2 h. A solution of 1-bromo-3-chloropropane (12.5 mL, 126 mmol) in THF (120 mL) was then added dropwise and the mixture was stirred at RT for 16 h. The mixture was poured into 0.5 M aq. NaOH solution (450 mL), the product extracted into ether (3 * 500 mL), and the combined organic extracts were dried over K2CO3, filtered and concentrated in vacuo to afford 2,3,5,6,7,8-hexahydro-1H-indolizin-4-ium chloride as a yellow-orange solid (18.0 g, 94%). Rf 0.65 (100:10:1 CHCl3:MeOH:aq. NH3 (18 M)); numax (thin film)/cm-1 3396w, 2950s, 2867 m, 1644s, 1431 m, 1303 m, 1015w; deltaH (400 MHz, C6D6) 1.38 – 1.61 (6 H, m), 1.89 – 2.00 (4 H, m), 3.12 (2 H, t, J 6.5), 3.73 (2 H, app. tquin, J 7.5, 5.5, 2.0); deltaC (100 MHz, C6D6) 22.8, 23.7, 32.5, 32.7, 37.3, 44.8, 61.3, 175.5; m/z (ESI+) 162 (M(37Cl)H+, 32%), 160 (M(35Cl)H+, 100), 124 ((M – Cl)+, 35). To a stirred solution of the iminium salt (9.00 g, 56.4 mmol) in water (900 mL) was added powdered NaOH (56.4 g, 1.41 mol) and the reaction mixture was stirred at RT for 16 h. Pentane (900 mL) was added and the mixture was stirred at RT for 1 h. The separated organic layer was dried over K2CO3, filtered and concentrated in vacuo to afford the title compound as a colourless oil (5.15 g, 74%). numax (thin film)/cm-1 2930s, 1683 m, 1648w, 1445w, 1280m, 1185 m; deltaH (400 MHz, C6D6) 1.47 – 1.56 (2 H, m), 1.81 – 1.88 (2 H, m), 2.12 – 2.18 (2 H, m), 2.24 – 2.31 (2 H, m), 2.66 (2 H, t, J 6.5), 2.80 (2 H, t, J 5.5), 4.43 (1 H, tt, J 3.5, 1.5); deltaC (100 MHz, C6D6) 21.9, 22.4, 23.5, 29.2, 47.1, 53.1, 88.2 (4 carbon not observed); m/z (ESI+) 124 (MH+, 100%)., 872-32-2
872-32-2 2-Methyl-1-pyrroline 70103, apyrrolines compound, is more and more widely used in various fields.
Reference£º
Article; Seah, Kang Yee; Robertson, Jeremy; Tetrahedron; vol. 75; 46; (2019);,
Pyrroline – Wikipedia
1-Pyrroline | C4H7N – PubChem