Dealing with Coworkers

As a young MIS officer and IT personnel of our college, i always had a hardtime dealing with coemployees who loves to wallow in their negativism and laziness. Reporting to the top management of their irresponsibility after several attempts of reminding them their part in my projects resulted in ruined relationship and worst of all heated arguments. I always regret the fact that they are older and had rendered longer years of service than me. Late submission of reports and compliance to my requests is my greatest problem. Any advice please?