Possible reverse 1031 exchange

[Steve Richards]

I have a rental condo that has just been voted to be deconverted, so the building is being bought out.   The closing will not take place for at least another 60 days since the new owners  are doing their due diligence. Since the property is technically sold (75% majority voted to approve) but the closing won't take place for another 60 days how can I structure a 1031exchange on a property that I have already identified and will close on before I received the closing check on the old property. 

Thanks 

Steve