Blueberry Challah

2 cups blueberries
1 1/4 cups granulated sugar, divided
1 1/4 cups water, divided
1 tablespoon yeast
10 cups white bread flour, divided
1 1/2 teaspoons salt
1/2 pound margarine
3 eggs
2 egg yolks

Mix blueberries with 1/2 cup sugar and 14 cup water. Cook over low heat, stirring occasionally, until the sugar is dissolved. Cool and pure