Abstract
A mild, efficient, and highly regio- and stereoselective method for the methoxy and ethoxy bromination of olefins has been developed using NH4Br as a bromine source and Oxone as an oxidant. Various kinds of olefins (aromatic, linear, and cyclic olefins) afforded the corresponding alkoxy brominated products in moderate to excellent yields.
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GRAPHICAL ABSTRACT
ACKNOWLEDGMENT
M. A. K. and M. N. acknowledge the financial support from the Council of Scientific and Industrial Research, India, in the form of fellowships.
Notes
a Styrene (2 mmol), NH4Br (2.2 mmol), Oxone (2.2 mmol), ROH (10 mL).
b Isolated yields.
c At room temperature.
d At 80 °C.
a Isolated yields.
b Olefin (2 mmol), NH4Br (2.2 mmol), Oxone (2.2 mmol), MeOH (10 mL) at room temperature.
c Olefin (2 mmol), NH4Br (2.2 mmol), Oxone (2.2 mmol), EtOH (10 mL) at reflux temperature.
d At room temperature.
e Dibromo product.
f erythro products.
g threo products.
h Molar ratio of erythro and threo 62:38, determined by 1H NMR.
i Molar ratio of threo and erythro 33:67, determined by 1H NMR.
a Isolated yields.
b Olefin (2 mmol), NH4Br (2.2 mmol), Oxone (2.2 mmol), MeOH (10 mL) at room temperature.
c Olefin (2 mmol), NH4Br (2.2 mmol), Oxone (2.2 mmol), EtOH (10 mL) at reflux temperature.
d At room temperature.
e Dibromo product.