Not able to substituent value of ENV in RUN instruction

Hi All,

My Docker File is as below:

FROM ubuntu:latest
ENV content="DCA Certified"
RUN ["/bin/bash","-c","echo 'I am ${content}'> /tmp/status.txt"]

My Image is getting build successfully using docker image build command but when i spin the container, I DO NOT see the value of ENV variable substituted in file status.txt

CAT status.txt = i am ${content}

Suggestions are appreciated