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Stannous chloride dihydrate (22.6 parts) was treated with industrial methylated spirits (70 parts) and heated to 60° to dissolve. The above ester (6.5 parts) was dissolved in industrial methylated spirits (2.8 parts) and run in to the hot solution of tin salt at such a rate as to maintain a gentle reflux (30 minutes). Finally the mixture was heated at reflux for 3 hours. After cooling, solvent was evaporated, and the residue treated with ethyl acetate (125 parts), and stirred in an ice bath. Ammonia (density 0.880 g/ml, 15 parts) was run in, keeping the temperature below 20°, and finally stirring at ambient temperature for 1 hour before filtering. The filtered tin salts were washed with two portions of ethyl acetate (each 45 parts), and the organic solvent evaporated. The oily residue was purified by chromatography on silica, eluting initially with dichloromethane:hexane 3:1, then 1:1, and finally with dichloromethane. Appropriate fractions were combined to give allyl 3-allyloxy-4-aminobenzoate (4.2 parts, 73%).

1. temperatureheated to 60°
2. dissolutionto dissolve
3. temperatureto maintain
4. temperaturea gentle reflux (30 minutes)
5. temperatureFinally the mixture was heated
6. temperatureat reflux for 3 hours
7. temperatureAfter cooling
8. customsolvent was evaporated
9. additionthe residue treated with ethyl acetate (125 parts)
10. customthe temperature below 20°
11. stirringfinally stirring at ambient temperature for 1 hour
12. filtrationbefore filtering
13. washThe filtered tin salts were washed with two portions of ethyl acetate (each 45 parts), and the organic solvent
14. customevaporated
15. customThe oily residue was purified by chromatography on silica
16. washeluting initially with dichloromethane:hexane 3:1