General procedure for the synthesis of p-toluenesulfonic acid-β-chloroethyl ester from p-toluenesulfonyl chloride and 2-chloroethanol:
1. 180mL of dichloromethane (DCM) was added to a 1L round bottom flask (RBF) to which p-toluenesulfonyl chloride (172g, 0.884mol) and pyridine (59g, 0.75mol) were added, and the flask was cooled in an ice bath for about 5 minutes.
2. 2-chloroethanol (40.3 g, 0.496 mol) was added slowly, then the flask was removed from the ice bath and stirred at room temperature (r.t.) for 15 hours.
3. The reaction mixture was poured into a 1 L dispensing funnel and washed sequentially twice with a mixture of 300 mL of water plus 50 mL of pyridine, and then washed with 300 mL of water plus 75 mL of aqueous hydrochloric acid 36% wt (the aqueous phase was discarded after each wash).
4. The solvent was removed under reduced pressure to afford analytically pure p-toluenesulfonic acid-β-chloroethyl ester (1) as a pale yellow, thick, syrupy product (116 g, 0.494 mol, 100% yield).
1H NMR data: δ= 7.81 (d, 2H, aromatic, interstitial with CH3, J = 8.3 Hz), 7.37 (d, 2H, aromatic, adjacent to CH3, J = 8.3 Hz), 4.23 (t, OCH2, J = 5.9 Hz), 3.66 (t, CH2Cl, J = 5.9 Hz), 2.46 (s, CH3).
