Tosco Corp., which owns and operates thousands of Circle K convenience stores and has nearly 5,000 employees in Arizona, is being acquired by Phillips Petroleum. The deal is expected to close later this year.

As a result of the merger, Tosco won't need a 170,000-sf, class-A office it recently had built and hasn't occupied. The company hired Ryan Cos. to build the six-story facility, which is at corner of Washington Street and Priest Drive. It is adjacent to the company's current 250,000-sf headquarters. The new building would have housed the marketing division, which has about 1,200 employees.

Even with the pending mergers, Tosco executives thought there would be enough company growth to warrant the additional space. But Phillips believes that hundreds of duplicate jobs between the two companies will be cut when the merger is completed, although it to keep the Tempe office open as a base for retail, marketing and transportation operations.

Now, Tosco has hired Cushman & Wakefield to search for a tenant for the 170,000 sf. Jim Wentworth, head of the Phoenix office of the brokerage firm, says the site would be ideal for a regional hub or corporate headquarters for a company with state-of-the-art technology needs.

It might also be good if the new tenants were football fans. Tempe expects to break ground in coming weeks on a $330-million, 73,000-seat football stadium for the Arizona Cardinals at the southeast corner of Priest Drive and Washington Street. Construction of the retractable doomed stadium is expected to last two years and very well could attract additional office and retail development to the area.