A Chicago developer known for turning vintage downtown buildings into hotels lines up an ambitious project for the 522-room inn, which sits atop an office building next to the future Salesforce Tower.

Murphy is leading a venture to acquire the leasehold interest in the 522-room Holiday Inn Chicago Mart Plaza atop the office building at 350 N. Orleans St., according to sources familiar with the property. The venture is finalizing a deal to pay close to $23 million, or around $43,000 per room, for the property, with an ambitious plan to renovate and reposition it with a more upscale brand, sources said.