# Have P-acyl phosphines ever been synthesized?

I've done some amount of searching and can't seem to find any evidence in the literature that there exists a phosphine analogue of carboxyl amides. I'm looking for compounds of the form $\ce{ R(C=O)PR_{2}}$; basically a moeity similar to a primary or secondy amide but with a phosphorous atom instead of a nitrogen.

I would also wonder what the proper name for these functionalities would be. Taking a shot in the dark I might guess "phosphomide", "acyl phosphine", or "acyl phosphinide".

I would like to specifically disqualify Acyl-phosphine oxides or any compounds where the acyl-connected phosphorous is also connected to an oxygen.

## 1 Answer

When I saw this question, I realized I couldn't remember ever seeing an acylphosphine, but I was curious and went looking. I found that they're actually quite easy to make. One common thing I saw was the use of trimethylsilylphosphines with acyl chlorides to form acylphosphines.

The easier method, however, was simply to react a substituted phosphine in the presence of triethylamine with an acyl chloride. The analogous reaction can be done with amines to form amides. In this paper, they describe the synthesis of P-acetyldiphenylphosphine using diphenylphosphine, triethylamine and acetyl chloride. They have some other examples in there, but this suggests that these compounds are typically fairly trivial to synthesize.

One more note: In my searches, I saw "acylphosphine," "acyl phosphide," and "phosphomide" as named. The paper I linked uses the term "phosphomide."