Reaction #1145

Reaction equation

5-[6-(5-methyl-2-phenyl-4-oxazolyl-methoxy)-2-benzofuranylmethylidene]-2,4-thiazolidinedione

→

5-[6-(5-methyl-2-phenyl-4-oxazolylmethoxy)-2-benzofuranylmethyl]-2,4-thiazolidinedione

Yield 38.0%

Solvents

tetrahydrofuran

Conditions

Workup

1. 1
   Otherwas subjected to catalytic reduction at room temperature under a hydrogen
2. 2
   Otherfor 8 hours
3. 3
   FiltrationAfter the catalyst was filtered off
4. 4
   FiltrationAfter the catalyst was filtered off
5. 5
   Concentrationthe filtrate was concentrated under reduced pressure
6. 6
   WashFrom the fraction eluted with ethyl acetate-chloroform (1:5

Procedure

A mixture of 5-[6-(5-methyl-2-phenyl-4-oxazolyl-methoxy)-2-benzofuranylmethylidene]-2,4-thiazolidinedione (0.80 g), palladium-carbon (5%, 1.60 g) and tetrahydrofuran (250 ml) was subjected to catalytic reduction at room temperature under a hydrogen pressure of 3.2 kgf/cm2 for 8 hours. After the catalyst was filtered off, the filtrate was subjected to catalytic reduction under constant conditions for additional 16 hours. After the catalyst was filtered off, the filtrate was concentrated under reduced pressure; the residue was subjected to silica gel column chromatography. From the fraction eluted with ethyl acetate-chloroform (1:5, v/v), crystals of 5-[6-(5-methyl-2-phenyl-4-oxazolylmethoxy)-2-benzofuranylmethyl]-2,4-thiazolidinedione (0.305 g, 38%) were obtained, which was then recrystallized from dichloromethane-methanol to yield yellow needles having a melting point of 179° to 180° C.

Source