Tetrahydrofuran → HCID 19991018, compound

HRID 346305Notes

Reaction equation

HRID 346305 reaction equation
[OH:1][C@@H:2]1[C@H:6]([CH2:7][CH:8]([CH3:10])[CH3:9])[NH:5][C:4](=[O:11])[CH2:3]1.O1CCCC1.[O:17]1[CH:22]=[CH:21][CH2:20][CH2:19][CH2:18]1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>ClCCl>[CH3:10][CH:8]([CH3:9])[CH2:7][CH:6]1[NH:5][C:4](=[O:11])[CH2:3][CH:2]1[O:1][CH:18]1[CH2:19][CH2:20][CH2:21][CH2:22][O:17]1

Participants

6

Reactant 4

HCID 8028TetrahydrofuranHCID 80803,4-dihydro-2H-pyranHCID 521998p-Toluenesulfonic acid monohydrateHCID 11768826HCID 11768826, compound

Product 1

HCID 19991018HCID 19991018, compound

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A mixture of 2.8 g (17.8 mmol) of (4S-cis)-4-hydroxy-5-(2-methylpropyl)-2-pyrrolidinone, 20 ml of tetrahydrofuran and 20 ml of dichloromethane is treated with 1.8 ml (19.7 mmol) of 3,4-dihydro-2H-pyran and 150 mg (0.79 mmol) of para-toluenesulfonic acid hydrate. The resulting solution is stirred at room temperature overnight and then partitioned between ethyl acetate and a 5% aqueous solution of sodium bicarbonate. The organic layer is separated, dried over magnesium sulfate, evaporated, and the residue filtered through a 175 ml bed of silica gel. Elution with hexane-ethyl acetate (1:1 then 1:2 and finally 0:1) affords 5-(2-methylpropyl)-4-[(tetrahydro-2H-pyran-2-yl)oxy]-2-pyrrolidinone, (pyranyl center R, S; other centers S) after evaporation from diethyl ether; mp 67°-69° C.

Workup

  1. custompartitioned between ethyl acetate
  2. customThe organic layer is separated
  3. dry with materialdried over magnesium sulfate
  4. customevaporated
  5. filtrationthe residue filtered through a 175 ml bed of silica gel
  6. washElution with hexane-ethyl acetate (1:1

Sources & evidence

ORD record
ord-8e60c2e646754b4e9b8c6d6d47a980f1
Source dataset
uspto-grants-1991_10
Patent number
US05061808

Reaction notes

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