Réaction #1552064

Équation de réaction

NaH

NaH

dimethyl sulfate

2-bromo-N-phenylaniline

15-crown-5

KBr

→

2-Bromo-N-methyl-N-phenylaniline

Solvants

dimethoxyethane

THF

Conditions de réaction

Traitement

1. 1
   TempératureAfter refluxing for 20 h under argon the reaction
2. 2
   Extractionextracted with Et2O (5×50 mL)
3. 3
   Lavagewashed thoroughly with saturated sodium bicarbonate (3×25 mL), brine and water
4. 4
   Séchagedried over MgSO4
5. 5
   Autrethe solvent evaporated under reduced pressure
6. 6
   AutreThe resulting oil was purified by flash column chromatography
7. 7
   Lavageelution
8. 8
   Autreto yield 2.5 g (80%)

Mode opératoire

A flame-dried two-neck round bottom flask was charged with 2-bromo-N-phenylaniline (3 g, 12.2 mmol), 0.1 mL 15-crown-5, 200 mL dry THF and 50 mL dimethoxyethane under argon. The solution was cooled to 0° C. in an ice bath, 0.6 g of a 60 wt % dispersion of NaH in mineral oil (0.36 g NaH, 15 mmol) was added to the reaction mixture in small portions under argon and 1.4 mL dimethyl sulfate (1.89 g, 15 mmol) was added via syringe. After refluxing for 20 h under argon the reaction was poured carefully onto 500 g ice and extracted with Et2O (5×50 mL). The organic layers were combined, washed thoroughly with saturated sodium bicarbonate (3×25 mL), brine and water, dried over MgSO4 and the solvent evaporated under reduced pressure. The resulting oil was purified by flash column chromatography using gradient elution, starting with 100% hexanes and progressing to 30% dichloromethane in hexanes to yield 2.5 g (80%)-of a clear oil. 1H NMR (400 MHz, CHCl3) δ 3.22 (s, 3H), 6.56 (d, J=7.6 Hz, 2H), 6.75 (t, J=7.6 Hz, 1H), 7.15 (m, 3H), 7.25 (dd, J=8.0 Hz, J=2.0 Hz, 1H), 7.32 (td, J=7.6 Hz, J=1.2 Hz, 1H), 7.66 (dd, J=8.0 Hz, J=1.6 Hz, 1H). 13C NMR (100 MHz, CHCl3) δ 39.1, 113.5, 117.8, 124.4, 127.9, 128.4, 129.1, 129.2, 130.6, 134.3, 147.0, 148.7. HRMS (ESI) calc for C13H12BrN [M+H]+ 262.0226, found 262.0234. IR (KBr plate) 654 (s), 691 (s), 748 (s), 872 (s), 1139 (s), 1137 (s), 1273 (s), 1346 (s), 1438 (m), 1467 (s), 1499 (s), 1580 (s), 1601 (s), 2813 (m), 2824 (s), 3058 (m), 3089 (m) cm−1.

Source