IUPAC by default linebreaks at hyphens.
From the chemmacros v5.8b manual:
The character - inserts a small space before the hyphen and removes a small space after it. Also usually words with hyphens are only allowed to break at the hyphen. Inside \iupac the hyphen will not prevent further hyphenation. The amount of inserted space can be customized.
Is there a way to prevent this? For example, in \iupac{2-alkenyl-1-alkynylbenzenes} I don't want a line break after the initial 2.
(Contrived) example of the problem:
\documentclass[letterpaper]{article}
\usepackage[left= 10 cm, right=5 cm]{geometry}
\usepackage{chemmacros}
\begin{document}
Gold-catalyzed (4+3)-annulations of \iupac{2-alkenyl-1-alkynylbenzenes} with anthranils with alkyne-dependent chemoselectivity: skeletal rearrangement versus non-rearrangement
\end{document}

