# Chemmacros - Multiple Values as coupling constant

I'm using the chemmacros package for my thesis in chemistry. Now I want to write down NMR data. My peak is a double-double-duplett I have therefore 3 coupling constants. I use \NMRand \J in the \experimental enviroment but for multiple values for J it is not working.
It should look like this: J = 1.2, 2.3, 3.4 Hz I tried to put brackets around the values but it is not helping.

Here is the minimal example

\documentclass[english, 12pt]{scrartcl}
\usepackage{blindtext}
\usepackage{chemmacros}
\chemsetup{
modules=all
}
\chemsetup[spectroscopy]{
delta=ppm,
use-equal
}
\sisetup{
separate-uncertainty,
per-mode=symbol,
detect-all,
range-phrase=--
}
\begin{document}
\section{chapter 1}
\blindtext
\begin{experimental}
\NMR(500)[CDCl3]
\val{6.05--6.01}(ddd, \J 9.9, 4.2, 1.4)
\end{experimental}
\end{document}