p-Toluenesulfonic acid → 2H-Pyran, tetrahydro-2-(2-iodoethoxy)-

HRID 1383041Notes

Reaction equation

HRID 1383041 reaction equation
[O:1]1[CH:6]=[CH:5][CH2:4][CH2:3][CH2:2]1.[I:7][CH:8](O)C.C1(C)C=CC(S(O)(=O)=O)=CC=1.[C:22]([O-:25])([O-])=O.[K+].[K+]>CCOCC>[I:7][CH2:8][CH2:22][O:25][CH:6]1[CH2:5][CH2:4][CH2:3][CH2:2][O:1]1

Participants

6

Reactant 4

HCID 6101p-Toluenesulfonic acidHCID 80803,4-dihydro-2H-pyranHCID 11430Potassium CarbonateHCID 178599451-Iodoethanol

Product 1

HCID 111186622H-Pyran, tetrahydro-2-(2-iodoethoxy)-

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

Freshly distilled dihydropyran (Aldrich, 59.0 g, 0.7 mol) was added dropwise to a cooled solution of iodoethanol (Aldrich, 98 g, 0.57 mol) in Et2O (1 L) containing 0.1 g of p-toluenesulfonic acid (Eastman). The solution was then stirred for 1 h at 5°. Solid K2CO3 (Mallinckrodt, 5 g) was then added to the reaction mixture and the resulting suspension stirred an additional 1 h at RT. The reaction was then filtered and the remaining solid washed with Et2O (1 L). The organic solutions were combined and concentrated on a rotary evaporator (in a flask washed with 1% NEt3 in H2O). The crude 2-(2-iodoethoxy)tetrahydro-2-H-pyran (100 g, 68.9%) was used without further purification.

Workup

  1. stirringthe resulting suspension stirred an additional 1 h at RT
  2. filtrationThe reaction was then filtered
  3. washthe remaining solid washed with Et2O (1 L)
  4. concentrationconcentrated on a rotary evaporator (in a flask washed with 1% NEt3 in H2O)
  5. customThe crude 2-(2-iodoethoxy)tetrahydro-2-H-pyran (100 g, 68.9%) was used without further purification

Sources & evidence

ORD record
ord-7aa641c3f1c844ac85b5ba92271b12c8
Source dataset
uspto-grants-1989_02
Patent number
US04808625

Reaction notes

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