pandoc -f latex -t native
\newcommand\arrow\to
$a\arrow b$
^D
[Para [Math InlineMath "a\\to b"]]

pandoc -f latex -t native
\newcommand\pfeil[1]{\to #1}
$a\pfeil b$
^D
[Para [Math InlineMath "a\\to b"]]

pandoc -f latex -t native
\newcommand\fleche{\to}
$a\fleche b$
^D
[Para [Math InlineMath "a\\to b"]]