ortho-Substitution Rearrangement of Benzyltrimethylammonium Ion by the Methylsulfinyl Carbanion¹

Heterobenzyl quaternary ammonium salts. IV. 2-Thenyl group as terminus and migrating moiety in the Stevens and Sommelet rearrangements of a quaternary ammonium ion

“…N-(2-Thenyl)dimethylamine (15). The reaction between dimethylformamide (DMF), formic acid (FA, 80%), and 35 gave practically none of the expected product,31 but when DMF (0.96 mol) was refluxed with FA (21 ml) and water (20 ml) for 3 h and then the aldehyde was added and refluxed for 6 h, workup of the mixture and distillation gave 15 in 52% yield, based on reacted 35: bp 71 °C ( 14Torr); ir 3050 vw, 2950 m, 2850 s, 2770 s, 1660 m, 1440 m, 1362 vw, 1343 w, 1305 m, 1277 w, 1258 m, 1230 s, 1215 m, 1188 m, 1129 w, 1098 w, 1038 s, 1008 w, 888 m, 855 w, 823 w, 766 m, 710 m, 704 s, 663 cm-1 m; NMR (CC14) 7.04 (m, 1 H), 6.77 (m, 2 H), 3.53 (s, 2 ), 2,16 (s, 6 H); MS (70 eV) m/e 97 (100, C5H6S+), 141 (36, M+), 140 (29), 58 (28, C2H2S+), 42 (24, CH2=N=CH2+), 45 (19, HNMe2+), 53 (17), 98 (16), 39 (15, C3H3+), 44 (13, NMe2+), 99 (9), 27 (7, C2H3+) and 41 (7); doubly charged ion at 70.5, metas table ions at 15.5 (58 -* 30) and 66.8 (M+ -C6H6S+).…”

“…AT,lV-Di(2-thenyl)dimethylammonium Iodide (9b). To a fresh solution of 2-thenyl iodide (98 mmol) in acetone (160 ml) was added 15 (98 mmol); the mixture was refluxed for 90 min while excluding oxygen and light. The yellow precipitate was filtered, washed with dry acetone, and recrystallized from 1-propanol.…”

“…The residue was taken up with hydrochloric acid and ether, and the aqueous solution was filtered through Celite, then made strongly alkaline with solid KOH. 14 was extracted with ether and distilled: 31 mg, bp 109-113 °C (0.15 Torr); mp 40-41 °C; ir 3070 vw, 2960 m, 2830 m, 2770 m, 2720 m, 1674 w, 1595 vw, 1480 vw, 1420 m, 1405 m, 1360 w, 1298 w, 1233 m, 1190 w, 1143 m, 1108 w, 1075 w, 1038 m, 1005 m, 888 vw, 867 vw, 851 w, 824 m, 764 w, 741 m, 725 m, 695 cm-1 s (broad); NMR (CC14) 6.90 (m, 5 H), 4.54 (s, 1 ), 2.41 (s, 3 H), and 2.16 (s, 6 H);!H NMR [CC14 + Eu(fod)3] 8.86 (pseudo-d, 1 H, 5.5 Hz), 7.88 (pseudo-s, 1 H), 7.39 (m, 2 ), 7.06 (d of d, 1 H, J = 3.5 Hz), 6.29 (s, 1 H), 4.30 (s, 3 H), and 2.91 (s, 6 H); MS (70 eV) m/e 193 (100, M+ --NMe2), 194 (28), 192 (22), 195 (19), 160 (15), 147 (12), 134 (7), 140 (7), 115 (7), 59 (7),..., 237 (3, M+); MS (20 eV) m/e 193 (100), 192 (24), 194 (15), 195 (7), 222 (3, M+ -Me), 237 (2, M+).…”

“…a methyl group of the Sommelet or the Stevens type, which from 1 gave 3 or 2 and 4, would lead from 9 to 10 or 11 and 12, respectively. The rearrangements of 5 via Stevens or Sommelet routes to 6 or 7 and 8 would find parallels in respective formation of 13 or 14 and 10 from 9, Displacement or cleavage would re-form the synthetic precursor of 9, N,N-dimethyl-N-(2-thenyl)amine (15). Synthesis of di(2-thenyl) starting materials and anticipated products is discussed in Part B.…”

“…In order to be absolutely certain that other possible products were not present in small amounts which might be obscured by overlapping peaks in GLG analyses of 13 and 14, amines 11,12, and 41 were prepared (Scheme IV) and their Scheme IV RLi iV-(2-Thenyl) -N-methyl- (15) °Retention time ratios vs. a known standard are given. b 2 m by 0.25 mm packed with Igepal CO 880 5% on Chromosorb W, 60-80 mesh, 180 °C, flow rate 6-8 ml/min nitrogen.…”