tcolorbox in RMarkdown with shortcuts - pdf

Question

I'm using the LaTex library tcolorbox in a RMarkdown document to list R code with tbclisting{...}. It works fine when I use the full command is used in the document
\begin{tcblisting}{colback=red!5!white, colframe=red!50!black,listing only,before skip=5 cm,
title=R code for finding and plotting frequencies from sorted data - Figure 3.5,hbox, enhanced, drop fuzzy shadow, listing options={language=R,keywordstyle=\color{blue}},before=\begin{center}, after=\end{center}}
some text
\end{tcblisting}
Due to the length of the command and the multiple use of similar boxes, changing each box to reflect, say, a new color, is tedious and error prone. I'd like to create a short cut using
\newtcblisting{mybox}[1]{%colback=red!5!white, colframe=red!50!black,listing only,before skip=5 cm,title={#1},hbox, enhanced, drop fuzzy shadow, listing options={language=R,keywordstyle=\color{blue}}, before=\begin{center}, after=\end{center}}
in the preamble as in the LaTex documentation, then implemented using
when I refer to the predefined box using
\begin{mybox}{my box title}
some text
\end{mybox}
but the compiler-to-pdf gives me an error message
**!Package pgfkeys Error: I do not know the key '/tcb/[' and I am going to ignore it. Perhaps you misspelled it.**
I'm thinking that 1) RMarkdown/tcolorbox doesn't support this or 2) something is wrong with my syntax. For 2) I've tried putting the newtcblisting definition in the preamble header-includes: section with the "-" preceding it (no good) and in the main body of the document w/o the "-". Also no good.
Can anyone help with this?