# one line
for f in *png; do fn=$(basename $f); d="${fn%.*}"; echo $d; mkdir $d; mv $f $d; done
#
# Expanded with explanations
#
# list of files
for f in *png; do
# get the file name without the path
fn=$(basename $f);
# get just the filename root, without the extension
d="${fn%.*}"
# output to screen so that we know something is going on
echo $d
# make the directory
mkdir $d
# move the file into the directory
mv $f $d
# close the loop
done