p-Toluenesulfonic acid → Flavanone, (+)-

HRID 2263645Notes

Reaction equation

HRID 2263645 reaction equation
[OH:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[C:8](/[C:10](=[CH:18]\[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)/C(OC(C)(C)C)=O)=[O:9].C1(C)C=CC(S(O)(=O)=O)=CC=1>NC(N)=S.C1(C)C=CC=CC=1>[O:1]1[C:2]2[C:3](=[CH:4][CH:5]=[CH:6][CH:7]=2)[C:8](=[O:9])[CH2:10][C@@H:18]1[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1

Participants

5

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 16125842(E)-tert-butyl 2-(2-hydroxyphenylcarbonyl)-3-phenylprop-2-enoate

Product 1

HCID 689010Flavanone, (+)-Yield 92%

Reagents, catalysts & solvents 2

HCID 2723790ThioureaCatalystHCID 1140TolueneSolvent

Procedure

Prepared according to general procedure using (E)-tert-butyl 2-(2-hydroxyphenylcarbonyl)-3-phenylprop-2-enoate (5) (65 mg, 0.2 mmol) and thiourea catalyst III (14 mg, 0.02 mmol) in 2.0 mL toluene for 36 h at −25° C. and p-toluenesulfonic acid (19 mg, 0.10 mmol) for 24 h. Purification via column chromatography with 10% EtOAc/hexanes afforded 41 mg (92%) of 7 as a white solid in 94% ee. [α]D: +55.6 (EtOH, c=0.5). Analytical data match those reported in the literature.

Workup

  1. customPrepared
  2. customfor 36 h
  3. customat −25° C.
  4. customPurification via column chromatography with 10% EtOAc/hexanes

Sources & evidence

ORD record
ord-87feac1881f54c9b9d5a30ad41bbf897
Source dataset
uspto-grants-2010_12
Patent number
US07851640B2

Reaction notes

Loading…