Exemption of capital gain tax under section 54

I have sold a property on which there is certain capital gains, I wish to know whether I can save tax on this capital gain by buying an undivided share in property (residential flat) booked in the name of my wife whose all payment have been made by my wife but possession is about to happen. Builder has also agreed to add my name in the property as joint owner and accordingly registration of the property will also be in joint name. Kindly advise urgently.