Financing for Fluor’s property sale was advanced.

The engineering company’s previously reported plan to sell and develop its Irvine headquarters property got a boost as Winthrop Financial Associates, a Boston real estate investment banking firm, formed a partnership with an affiliate of the Trammell Crow development company to raise money for the project. Trammell Crow and Winthrop have been working on the financing proposals for several months. Fluor will get $340 million from the sale and will lease back a portion of its corporate headquarters. The sale is part of Fluor’s strategy to raise cash by selling assets. Escrow is scheduled to close on or before July 31.