Butyl bromide → 1-butylazepane

Participants

Reaction Steps

Procedure 1a—The first N-substitution of azepane was carried out using butyl bromide as an N-alkylating agent to form 1-butylazepane. To a stirring solution of azepane (49.97 g, 503.8 mmol) in methanol (220 cm3) cooled in an ice-water bath was added dropwise 1-bromobutane (57 cm3, 530 mmol), and then potassium carbonate (72.5 g, 524 mmol). The mixture was vigorously stirred at room temperature for 24 h. The resulting suspension was filtered through a sintered glass fret and the solution concentrated under reduced pressure at 45° C. in a rotary evaporator. A yellowish suspension was thus obtained and distilled in vacuo (45-47° C., 5.5 mmHg) to give 1-butylazepane as a colourless liquid (50.30 g, 64.3%). δH (500.13 MHz, CDCl3) 2.62 (4H, t, 3J(H,H)=5.5 Hz), 2.45 (2H, m), 1.64 (4H, br m), 1.59 (4H, br m), 1.45 (2H, m), 1.30 (2H, sextet, 3J(H,H)=7.4 Hz), 0.90 (3H, t, 3J(H,H)=7.4 Hz); δC (125.76 MHz, CDCl3) 58.2, 55.7, 29.8, 28.0, 27.1, 20.9, 14.1. ESI-MS: m/z=156 [M+H]+ (100). Calcd. for C10H22N: 156.1752; found: 156.1755.

Provenance & Evidence