Reaktion #462022

Reaktionsgleichung

1-Adamantanemethanol

4-hydroxyphenylacetic acid

p-toluenesulfonic acid

water

→

(adamant-1-yl)methyl 4-hydroxyphenylacetate

Lösungsmittel

benzene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto cool
2. 2
   Waschenwas washed, first with water (100 mL)
3. 3
   TrocknenDrying over anhydrous MgSO4
4. 4
   Filtrationfiltering
5. 5
   Einengenconcentrating in vacuo

Vorschrift

1-Adamantanemethanol (8.31 g, 0.05 mol), 4-hydroxyphenylacetic acid (7.6 g, 0.05 mol) and p-toluenesulfonic acid (1 g, 0.006 mol) were refluxed in benzene (100 mL) with continuous water separation for 8 hours. The reaction mixture was allowed to cool with stirring overnight, then was washed, first with water (100 mL), then with aqueous 5% NaHCO3 solution (100 mL), then twice more with water (100 mL). Drying over anhydrous MgSO4, filtering and concentrating in vacuo afforded (adamant-1-yl)methyl 4-hydroxyphenylacetate, which was then combined with epichlorohydrin (50 mL) and refluxed for 2 hours in the presence of DBU (1 mL, 0.007 mol). Excess epichlorohydrin was removed in vacuo. The oily residue was dissolved in acetonitrile (100 mL) and combined with isopropylamine (20 mL, 0.23 mol). The resultant reaction mixture was refluxed for 4 hours. The oily brown residue was partitioned between ethyl ether (100 mL ) and 1 M aqueous KOH solution (100 mL). The ether layer was separated and to it was added 1N HCl (30 mL). The resultant acid layer was separated and to it were added ethyl ether (100 mL) and 1M aqueous KOH solution (30 mL). The resultant ether layer was separated, dried over anhydrous MgSO4, filtered and evaporated in vacuo to give the free amine base as a crude product. The crude product (5.g, 72.5% yield) was dissolved in acetone (25 mL), and oxalic acid (1.8 g) in acetone (25 mL) was added dropwise, with stirring. The mixture was allowed to stir for 24 hours with additional acetone. The acetone solution was evaporated and the oily residue was partitioned between ether (100 mL) and 1M aqueous KOH solution (100 mL). The ether solution was dried over anhydrous MgSO4, filtered and concentrated. The oily residue was dissolved in acetone and an equivalent amount of oxalic acid in acetone was added dropwise. The oxalate salt of (adamant-1-yl)methyl-4-(2-hydroxy- 3-isopropylamino)propoxyphenylacetate which separated was removed and dried. It melted at 55°-57° C. NMR and elemental analysts were consistent with structure. The free base has the formula: ##STR299##

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