[Nekromantis]

Hi, I have to write a mechanism Heck reaction but not circle mechanism. I Have a two compounds.

It's correct?

[opsomath]

Your curvy arrows are kind of messed up. Remember, an arrow always:

1) Starts at an electron pair

2) Goes to an electron acceptor

So, things are screwy in your third step where you are trying to eliminate the Pd complex. You should show it doing a beta-hydride elimination; check out the wikipedia for Heck reaction.

[Nekromantis]

now is correct?

[opsomath]

Not quite. You want the Pd to be the leaving group.

[Nekromantis]

So how should be do