Can one buy property in other's from sale proceed of existing property

Yes.  It is your flat you can sell it and you can buy another property in the name of your spouse.

Under Section 54 the IncomeTax Act, an individual or HUF selling a residential property can avail tax exemptions from Capital Gains if the capital gains are invested in purchase or construction of residential property. 
 

• The property must only be bought on the name of the seller and not on anybody else’s name.
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