Lawesson's reagent → 7-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-3-methyl-isobenzofuran-1(3H)-thione

HRID 1729161Notes

Reaction equation

HRID 1729161 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[C:7]([O:9][CH3:10])[N:6]=[C:5]([O:11][C:12]2[CH:13]=[CH:14][CH:15]=[C:16]3[C:21]=2[C:19](=O)[O:18][CH:17]3[CH3:22])[N:4]=1.COC1C=CC(P2(=S)SP(C3C=CC(OC)=CC=3)(=S)[S:32]2)=CC=1>C1(C)C(C)=CC=CC=1>[CH3:1][O:2][C:3]1[CH:8]=[C:7]([O:9][CH3:10])[N:6]=[C:5]([O:11][C:12]2[CH:13]=[CH:14][CH:15]=[C:16]3[C:21]=2[C:19](=[S:32])[O:18][CH:17]3[CH3:22])[N:4]=1

Participants

4

Reactant 2

HCID 87949Lawesson's reagentHCID 199274867-[(4,6-Dimethoxy-pyrimidin-2-yl)oxy]-3-methyl-phthalide

Product 1

HCID 199274637-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-3-methyl-isobenzofuran-1(3H)-thione

Reagents, catalysts & solvents 1

HCID 7237O-XyleneSolvent

Procedure

A mixture of 6.35 g of 7-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-3-methyl-phthalide (see Example 1) and 8.92 g of 2,4-bis(4-methoxyphenyl)-2,4-dithioxo-1,3,2,4-dithia-diphosphetan (Lawesson reagent) is maintained at reflux temperature for approximately 16 hours in 40 ml of xylene. The reaction material is then filtered over silica gel (eluant: 30% diethyl ether/n-hexane) and recrystallised from ethyl acetate/n-hexane to yield 7-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-3-methyl-isobenzofuran-1(3H)-thione in the form of yellow crystals, m.p. 163°-164° C.; IR spectrum (CHCl3): 1602, 1570, 1358, 1304, 1195 cm-1 ; 1H-NMR (CDCl3): 5.80 ppm (q, 1H), 1.71 ppm (d, 3H).

Workup

  1. temperatureis maintained
  2. filtrationThe reaction material is then filtered over silica gel (eluant: 30% diethyl ether/n-hexane)
  3. customrecrystallised from ethyl acetate/n-hexane

Sources & evidence

ORD record
ord-f56d05e5865842978b97f868262b368b
Source dataset
uspto-grants-1994_07
Patent number
US05332717

Reaction notes

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