Phenylsulfamate → Sulfamic acid 2-(3-pyridinyloxy)ethyl ester

A mixture of 4.9 g (0.035 mole) of 2(3-pyridinyloxy)ethanol (Preparation 18) and 8 g (0.046 mole) of sulfamic acid phenyl ester (Example 33) in 100 ml of dioxane was heated at reflux temperatue for 20 min. and the solvent then evaporated. The residue was triturated with 250 ml of acetone, filtered, and the filtrate acidified with a solution of anhydrous hydrogen chloride in isopropyl alcohol and the sticky brown precipitate collected. The brown solid was redissolved in 125 ml of methanol and diluted with 125 ml of ethanol. The solution was stirred with charcoal, filtered, and the filtrate partially evaporated to give a suspension. The suspension was diluted with isopropyl alcohol-isopropyl ether and filtered. The solid was dried at 50° C. for 18 hr and then at 70° C. for 18 hr in a vacuum oven. The yield was 4.5 g of solid title compound as the monohydrochloride, mp 156°-157° C.

1. temperaturewas heated
2. temperatureat reflux temperatue for 20 min.
3. customthe solvent then evaporated
4. customThe residue was triturated with 250 ml of acetone
5. filtrationfiltered
6. customthe sticky brown precipitate collected
7. dissolutionThe brown solid was redissolved in 125 ml of methanol
8. additiondiluted with 125 ml of ethanol
9. filtrationfiltered
10. customthe filtrate partially evaporated
11. customto give a suspension
12. filtrationfiltered
13. customThe solid was dried at 50° C. for 18 hr

ORD record

ord-03761f4de37a4346a1b5efe9f3c50d3b

Source dataset

uspto-grants-1993_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05192785