Bull.Chem.Soc.Jpn., 68,1.1995;297-300 K
2CO
3 / Me
3N
.HCl
preparation of 2-Propynyl p-Toluenesulfonate 2aTo a stirred suspension of propargyl alcohol (5.6 g, 0.1 mol) and K
2CO
3 (15.2 g, 0.12 mol) in MIBK (50 mL) was added Me
3N
.HCl (0.96 g, 0.01 mol) at 0-5°C. After 5 min, p-toluenesulfonyl chloride (20.97 g, 0.12 mol) in MIBK (50 mL) was added at 0-5°C for an hout. After the mixture was stirred for an hour, water (100 g) was added at 20°C. The separated water phase was back extracted with MIBK (20 mL) and the combined organic extracts were first washed with water, and then, saturated aquaeous NaCl, dried (Na
2SO
4), concentrated, and purified by column chromatography (hexane/EtOAc=10:1) giving 19.13 g (91%) of the sulfonate
2a.
MIBK = methyl isobutyl ketone
Here's some other alternatives to Py / Et
3N :
Bull.Chem.Soc.Jpn., 63,4.1990;1260-1262 NaOH / THF
synthesis 1999,9;1633-1636 TMEDA / Me
2N-(CH
2)
n-NMe
2 n=3, n=4, n=6 ;; shitty scan but you get the idea.
Synthesis - 1997;1433-1438 DABCO
Tetrahedron Lett., 42.2001;8781-8783 Ag
2O / KI
--
psyloxy--