Does a divorce agreed upon in exchange for the wife buying the husband's share in the house take effect, then she reneged on the agreement and did not buy the share?

Talaq (divorce) for compensation, such as saying, "I divorce you for such and such an amount," is considered a divorce by the majority of scholars. Some have gone to say that it is khul' (a form of divorce initiated by the wife) and is not counted as a talaq. However, an agreement between the spouses for divorce in exchange for the wife buying her husband's share of the house is not considered compensation for the divorce; rather, it is in exchange for the share. Thus, it is a revocable divorce (talaq raj'i). The woman is religiously obligated to fulfill her promise and buy the share.