[i3] append layout works from commandline, but not from .i3/config

[i3 . thegrue]

Hello,

I have a layout stored in emacs.json (attached). When I run this command from
the commandline, everything works fine:

markus@haktar % i3-msg 'append_layout /home/markus/.i3/emacs.json'

But when I run this command from .i3/config, one placeholder is missing: the
one in the horizontal container next to emacs:

exec --no-startup-id i3-msg 'workspace $wsp3;
append_layout /home/markus/.i3/emacs.json'

What am I doing wrong?

Thanks for your help,
-- 
Markus Grunwald

emacs.json
Description: application/json