I am working on a lab for my Organic Chemistry class which is on the synthesis of 1-bromobutane.

I am working on a lab for my Organic Chemistry class which is on the synthesis of 1-bromobutane. We are required to calculate the % yield which I am very familiar with doing but I am having a hard time figuring out what our theoretical yield should be in this specific scenario.. I understand that because this is a synthesis reaction we wont have a clear starting measurement to go off of for the 1-bromobutane so would the theoretical yield just be 1? We obtained 0.777 grams of product. Help! Thank you so much! I hope I provided enough information here