1-Phenethylamine, (+)- → (R)-5-(1-Phenyl-ethylamino)-3,6-dihydro-2H-pyran-4-carboxylic acid ethyl ester

HRID 1169236Notes

Reaction equation

HRID 1169236 reaction equation
[CH2:1]([O:3][C:4]([CH:6]1[CH2:11][CH2:10][O:9][CH2:8][C:7]1=O)=[O:5])[CH3:2].[CH3:13][C@@H:14]([NH2:21])[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1>C1C=CC=CC=1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>[CH2:1]([O:3][C:4]([C:6]1[CH2:11][CH2:10][O:9][CH2:8][C:7]=1[NH:21][C@@H:14]([C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1)[CH3:13])=[O:5])[CH3:2]

Participants

5

Reactant 2

HCID 6431891-Phenethylamine, (+)-HCID 21362493Ethyl 3-oxooxane-4-carboxylate

Product 1

HCID 59042158(R)-5-(1-Phenyl-ethylamino)-3,6-dihydro-2H-pyran-4-carboxylic acid ethyl esterYield 104.2%

Reagents, catalysts & solvents 2

HCID 521998p-Toluenesulfonic acid monohydrateCatalystHCID 241BenzeneSolvent

Procedure

A solution of 3-oxo-tetrahydro-pyran-4-carboxylic acid ethyl ester (3.03 g, 17.6 mmol), R-(+)-α-methylbenzylamine (2.35 g, 19.4 mmol) and p-toluenesulfonic acid hydrate (67 mg, 230 μmol) in benzene (60 mL) was heated at reflux under a Dean-Stark trap for 16 h . The cooled mixture was concentrated in vacuo to provide the product as a yellow oily semisolid (5.05 g), used without further purification. 1H NMR (300 mHz, CDCl3) δ8.97 (bd, J=7.3 Hz, 1H), 7.3-7.2 (m, 5H), 4.41 (m, 1H), 4.30 (d, J=16.1 Hz, 1H), 4.18 (q, J=7.3 Hz, 2H), 3.91 (d, J=16.1 Hz, 1H), 3.64 (m, 2H), 2.34 (m, 2H), 1.48 (d, J=6.5 Hz, 3H), 1.30 (t, J=7.3 Hz, 3H).

Workup

  1. temperatureat reflux under a Dean-Stark trap for 16 h
  2. concentrationThe cooled mixture was concentrated in vacuo

Sources & evidence

ORD record
ord-52d72601ed21492a95f4aa550facbb74
Source dataset
uspto-grants-2003_09
Patent number
US06627629B2

Reaction notes

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