What is the best way to brute force clear the transaction list ?

I'm intentionally not setting Success to true. 

JsonResult result = new JsonResult();
Dictionary<string, bool> response = new Dictionary<string, bool>();
response.Add("Success", false); // NOTE - Sending false. All (delete/update) confirmation to be done from the response back from server
result.Data = response;
return result;

But, I would like to clear prior transaction when the next SaveChange is called. I have autocommit to false, and have set the updateurl. I'm calling SaveChanges on all events (update, delete, add).