Which reagent is useful in the conversion of ethanenitrile to ethanal?

Collin's reagent is

The reaction shown below is known as:-
$C_6H_5COCl + H_2 \xrightarrow{Pd-BaSO_4} C_6H_5CHO + HCl$
(Benzoyl chloride $\rightarrow$ Benzaldehyde)

Reduction of acetyl chloride with $H_2$ in the presence of $Pd$ gives:

Ketones $(R-C(=O)-R_1)$ where $R = R_1 = \text{alkyl group}$. It can be obtained in one step by:

In the reaction $C_6H_6 + CO + HCl \xrightarrow{A} C_6H_5CHO + HCl$,what is $A$?