HCID 355613, compound → HCID 20251925, compound

HRID 481941Notes

Reaction equation

HRID 481941 reaction equation
CO[C:3]1[CH:8]=[CH:7][C:6]([CH:9]2[O:15][C:14]3[CH:16]=[C:17](OC)[CH:18]=[CH:19][C:13]=3[C:11](=O)[CH:10]2C2C=CC=CC=2)=[CH:5][CH:4]=1>[Pd].C(O)(=O)C>[CH:6]1([CH:9]2[CH2:10][CH2:11][C:13]3[CH:19]=[CH:18][CH:17]=[CH:16][C:14]=3[O:15]2)[CH2:5][CH2:4][CH2:3][CH2:8][CH2:7]1

Participants

4

Reactant 1

HCID 355613HCID 355613, compound

Product 1

HCID 20251925HCID 20251925, compound

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 176Acetic AcidSolvent

Conditions

Temperature
23 °C

Procedure

A suspension of the chromanone 2--2 (2.13 g, 9.25 mmol, 1 equiv) and 10% palladium on carbon (320 mg, 0.301 mmol, 0.0325 equiv) in acetic acid (20 mL) was heated at 70° C. under a hydrogen balloon for 16 h. After cooling to 23° C., the solids were removed by filtration through a pad of Celite® and were washed with ethyl acetate (100 mL). The filtrate was concentrated and the residue was purified by flash column chromatography (5% ethyl acetate in hexanes) to provide the benzopyran 2-3 as a colorless oil as well as recovered starting chromanone; 1H NMR (400 MHz, CDCl3), δ: 7.09 (m, 2H, ArH), 6.85 (m, 2H, ArH), 3.78 (m, 1H, OCH), 2.83 (m, 2H, ArCH2), 2.03 (m, 2H, ArCH2CH2 and CyH), 1.90-1.70 (m, 5H, ArCH2CH2 and CyH), 1.65 (m, 1H, CyH), 1.40-1.10 (m, 5H, CyH); TLC (5% ethyl acetate-hexanes), Rf =0.57 (UV).

Workup

  1. customthe solids were removed by filtration through a pad of Celite®
  2. washwere washed with ethyl acetate (100 mL)
  3. concentrationThe filtrate was concentrated
  4. customthe residue was purified by flash column chromatography (5% ethyl acetate in hexanes)

Sources & evidence

ORD record
ord-a148acbc7a204c07be7b86fa01fcee72
Source dataset
uspto-grants-1998_08
Patent number
US05792761

Reaction notes

Loading…