Reaction #11298

Reaction equation

2-(3-bromophenyl)-1,3-dioxolane

methanol

sodium hydride

Isatin

→

N-[3-(1,3-dioxolyl)phenyl]isatin

Solvents

chloroform

chloroform

DMF

Conditions

Workup

1. 1
   Temperaturecooled in an ice-bath under a nitrogen atmosphere
2. 2
   TemperatureThe resulting suspension was heated in an oil-bath under nitrogen at 130–140° C. for 16 hours
3. 3
   TemperatureIt was then cooled to room temperature
4. 4
   FiltrationThis suspension was filtered
5. 5
   Concentrationthe filtrate was concentrated under reduced pressure
6. 6
   OtherA viscous brown oil was recovered which
7. 7
   Otherwand evaporated to dryness
8. 8
   Othersuch for the next reaction

Procedure

Isatin (3.2 g, 0.0218 mol) was dissolved in anhydrous DMF (75 ml) and cooled in an ice-bath under a nitrogen atmosphere. To this cold solution, sodium hydride (0.575 g, 0.0239 mol) was added and the reaction was stirred at 0° C. for 1.5 hours. This solution was then treated with 2-(3-bromophenyl)-1,3-dioxolane (5 g, 1 equivalent) followed by CuI (8.3 g, 2 equivalents). The resulting suspension was heated in an oil-bath under nitrogen at 130–140° C. for 16 hours. It was then cooled to room temperature and diluted with an equal volume of chloroform. This suspension was filtered and the filtrate was concentrated under reduced pressure. A viscous brown oil was recovered which was suspended in xylenes (150 ml) wand evaporated to dryness. The residue was used as such for the next reaction. TLC (5% methanol in chloroform) showed clean conversion; Rf (product)=0.86.

Source