Abstract
A number of 4‐tosyloxycoumarins were treated with N‐methyl,N‐(2‐bromobenzyl)amine, and N‐methyl,N‐(2‐bromo‐5‐methoxybenzyl)amine in refluxing ethanol to give different 4‐[N‐(2′‐bromobenzyl),N‐methyl] amino coumarins in 70–75% yield. These tertiary amine substrates were then refluxed in dry benzene under nitrogen with tri‐n‐butyltin chloride and sodium cyanoborohydride in the presence of 0.5–0.6 mol equiv. of azobisisobutyronitrile(AIBN) for 4–5 hr to give the title compounds in 65–68% yield.
Acknowledgment
We thank the CSIR (New Delhi) for financial assistance. One of us (S.S.) is thankful to CSIR (New Delhi) for a Senior Research Fellowship.