3,4-dihydro-2H-pyran → methyl 2,2-dimethyl-3-(tetrahydro-2H-pyran-2-yloxy)propanoate

HRID 1893183Notes

Reaction equation

HRID 1893183 reaction equation
[CH3:1][O:2][C:3](=[O:9])[C:4]([CH3:8])([CH3:7])[CH2:5][OH:6].O.C1(C)C=CC(S(O)(=O)=O)=CC=1.[O:22]1[CH:27]=[CH:26][CH2:25][CH2:24][CH2:23]1.C([O-])(O)=O.[Na+]>COC(C)(C)C>[CH3:7][C:4]([CH3:8])([CH2:5][O:6][CH:23]1[CH2:24][CH2:25][CH2:26][CH2:27][O:22]1)[C:3]([O:2][CH3:1])=[O:9]

Participants

6

Reactant 4

HCID 80803,4-dihydro-2H-pyranHCID 84152Methyl 3-hydroxypivalateHCID 516892Sodium BicarbonateHCID 521998p-Toluenesulfonic acid monohydrate

Product 1

HCID 59253280methyl 2,2-dimethyl-3-(tetrahydro-2H-pyran-2-yloxy)propanoate

Reagents, catalysts & solvents 1

HCID 15413tert-Butyl methyl etherSolvent

Procedure

To a stirred mixture of hydroxypivalic acid methyl ester (50.0 g, 378 mmol) and p-toluenesulfonic acid monohydrate (1.439 g, 7.57 mmol) in 250 mL of methyl-tert-butylether was added dihydropyran (48.1 mL, 568 mmol) slowly with cooling. The mixture was stirred at room temperature overnight, 50 mL of saturated NaHCO3 added and the mixture shaken and separated. The organic layer dried over MgSO4 and concentrated. Purification of the residue by flash chromatography using 330 g column, 0%-5% ethyl acetate in hexane gave methyl 2,2-dimethyl-3-(tetrahydro-2H-pyran-2-yloxy)propanoate as a clear oil: 1H NMR (400 MHz, CDCl3) δ 4.5 (s, 1H), 3.8-3.6 (m, 2H), 3.6 (m, 3H), 3.4 (s, 1H), 3.25 (m, 1H), 1.7 (m, 1H), 1.6-1.18 (m, 5H), 1.05 (m, 6H).

Workup

  1. temperaturewith cooling
  2. stirringthe mixture shaken
  3. customseparated
  4. dry with materialThe organic layer dried over MgSO4
  5. concentrationconcentrated
  6. customPurification of the residue by flash chromatography

Sources & evidence

ORD record
ord-0ccd7e7439484ee0bcf83b0a806322d9
Source dataset
uspto-grants-2013_08
Patent number
US08513234B2

Reaction notes

Loading…