It is not easy to recover PdP4 (P = PPh3) from the catalytic mixture. In solution on most of the occasion, it turns into PdP2, a 14 electron species (by dissociating two Pd-P bonds and PPh3 will be in solution) to get ready for oxidation addition to form PdII square planar complex and catalytic process continued until elimination of desired coupled product takes place. It is highly unlikely to anticipate the formation of PdP4 after this process. After elimination, 14electron species (active catalyst) is ready for next cycle.

If you try to isolate, you may end isolating only oxidatively added PdII square planar complex.

Best wishes

Balakrishna