1-Bromo-3-chloropropane → 2-(6-Chloro-2-octynyloxy)tetrahydropyran

Participants

Reaction Conditions

Reaction Steps

A solution of 2-propynyloxytetrahydropyran (28.00 g, 0.200 mol) in dry THF (500 mL) at 0° C. was treated with n-BuLi (125 mL of a 1.6M solution, 0.200 mol) and stirred at 0° C. for 15 min. A solution of 1-bromo-3-chloropropane (31.50 g, 0.200 mol) in dry THF (50 mL) was added. The reaction mixture was warmed to room temperature and then refluxed for 20.5 h. The mixture was cooled, poured into a separatory funnel, and washed with two 200-mL portions of water. The organic layer was dried over Na2SO4 and concentrated by rotary evaporation to yield, after distillation (110°-112° C./0.4 torr), 35 as a colorless oil (38.80 g, 78%): IR (neat) 2950 (s), 2875, 2290 (w), 2230 (w), 1445, 1350, 1205, 1130 (s), 1120 (s), 1080, 1055, 1025 (s), 900, 870, 815 cm-1 ; 1H NMR (CDCl3) δ 4.79 (t, J=3.1 Hz, 1H), 4.25 (tq, J1 =15.3 Hz, J2 =2.2 Hz, 2H), 3.84 (dq, J1 =8.5 Hz, J2 =3.1 Hz, 1H), 3.66 (t, J=6.4 Hz, 2H), 3.53 (m, 1H), 2.43 (tt, J1 =6.8 Hz, J2 =2.1 Hz, 2H), 1.98 (p, J=6.6 Hz, 2H), 1.92-1.48 (m, 6H).

Provenance & Evidence