Reaction #2039

Reaction equation

(4Z)-1-(tetrahydropyran-2-yloxy)-4-decene

triphenylphosphine

bromine

→

product 17

Yield 90.0%

Z-1-Bromodec-4-ene

Yield 90.0%

Solvents

methylene chloride

CH2Cl2

Conditions

Workup

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   OtherIsolation and purification by conventional means

Procedure

To an ice-cool solution of triphenylphosphine (0.72 g, 2.74 mmol) and bromine (0.41 g, 2.6 mmol) in CH2Cl2, a solution of (4Z)-1-(tetrahydropyran-2-yloxy)-4-decene (16) (0.41 g, 1.71 mmol), prepared according to Example 16, in methylene chloride was added dropwise. Isolation and purification by conventional means afforded the product 17 in 90% yield (0.33 g). 1H NMR (200 MHz ) δ: 5.42 (dtt, J=11.0, 7.0, 7.0, 1.0, 1.0 Hz, 2H, CH=CH-4, 5); 3.41 (t, J=6.6, 6.6 Hz, 2H CH2 -1, 2.20 (dt, J=7.0, 7.0 Hz, 2H, CH2 -3); 2.04 (dr, J=6.5, 6.5 Hz, 2H, CH2 -6); 1.91 (tt, J=6.5, 6.5, 6.5 Hz, 2H, CH2 -2); 1.30 (m, 6H, CH2 -7, 8, 9); 0.89 (t, J=7.0 Hz, CH3). MS [EI, m/z(%)] 220 (M+ -8), 218 (M+, 8), 164 (12), 162 (12), 150 (23), 148 (23), 135 (8), 109 (12), 97 (44), 95 (14), 83 (55), 82 (14), 81 (37), 79 (15), 70 (21), 69 (100), 67 (39), 56 (29), 55 (93), 54 (20), 43 (21), 42 (20), 41 (92), 39 (30). IR (CCl4, cm-1) 3008 (cis CH=CH), 1246 (RCH2CH2Br), 649, 566 (C--Br).

Source