Grant permission to post a new node of content-type 2 if previous node of his content-type 1 has a state of approved
You can create two Roles.


Role 1 -> has permission to create summary (content type 1)
Role 2 -> has permission to create full article (content type 2)


you can assign Role 1 to users by default.

Next you create a rule like 


  Event : Summary gets approved
  Action : Add user role


The way you create the rule depends on whether you are using Workflow Node or Workflow field

If you are using Workflow Node then the rule  will be


  Event : Workflow state has changed 
  Condition : Check the state


If you are using Workflow Field then the rule will be


  Event : After updating existing node 
  Condition : Do a data comparison for the workflow field with the state ID.


Action will be Add user role, that is Role 2