Isoquinoline → isoquinolin-N-oxide

To a solution of isoquinoline (76.93 g, 595.6 mmol) in acetic acid (520 mL) was added portionwise every 10 min. 33.6 g of sodium perborate, NaBO3.4H2O. Over a 1 hour period a total of 201.6 g (1.31 mole) of perborate was added. The resulting mixture was stirred at 60° C. for 24 hours after which acetic acid was removed by passing a stream of air over the surface of the liquid contained in a large flat vessel overnight. The remaining solid was dissolved in 1 L of water and the solution neutralized with solid sodium bicarbonate. The solution was extracted with chloroform (3×300 mL) and the organic extracts dried over magnesium sulfate. Chloroform was evaporated and the residual white solid was redissolved in chloroform and precipitated by addition of hexane to give 65 g (75%) of the N-oxide: mp 138-140° C. (lit mp 141-142° C.)

1. customwas removed
2. dissolutionThe remaining solid was dissolved in 1 L of water
3. extractionThe solution was extracted with chloroform (3×300 mL)
4. dry with materialthe organic extracts dried over magnesium sulfate
5. customChloroform was evaporated
6. dissolutionthe residual white solid was redissolved in chloroform
7. customprecipitated by addition of hexane

ORD record

ord-1381bc80f19f48f886de81e8ed4878bf

Source dataset

uspto-grants-2004_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06825347B2