Formaldehyde → 5-[(2-Chloroethyl)(methyl)amino]-2-benzofuran-1(3H)-one

Temperature

0 °C

A mixture of 5-(2-chloro-ethylamino)-3H-isobenzofuran-1-one (3.0 g, 14.2 mmol), 37% formaldehyde aqueous solution (10 ml, 134 mmol) and sodium cyanoborohydride (3.6 g, 56.8 mmol) in a mixture of 10% AcOH aqueous solution (40 ml) and acetonitrile (40 ml) was stirred at 0° C. for 30 minutes. The mixture was allowed to warm to room temperature and was continuously stirred for 2 hours. The mixture was concentrated under reduced pressure, basified with 1M NaOH aqueous solution, and extracted with EtOAc (3×100 ml). The combined organic layers were washed with 1M NaOH aqueous solution (100 ml) and then water (2×100 ml), dried over anhydrous Na2SO4. Removal of the solvent led to a light yellow oil, which was crystallized with diethyl ether to produce 5-[(2-chloro-ethyl)-methyl-amino]-3H-isobenzofuran-1-one as a yellow solid (2.5 g, 78%).

1. temperatureto warm to room temperature
2. stirringwas continuously stirred for 2 hours
3. concentrationThe mixture was concentrated under reduced pressure
4. extractionextracted with EtOAc (3×100 ml)
5. washThe combined organic layers were washed with 1M NaOH aqueous solution (100 ml)
6. dry with materialwater (2×100 ml), dried over anhydrous Na2SO4
7. customRemoval of the solvent
8. customwas crystallized with diethyl ether

ORD record

ord-2035c2bebcc04e519c7cf1a756205fa7

Source dataset

uspto-grants-2006_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07060844B2