Butter a 7x11 inch baking pan. Separate biscuit dough into 8 pieces. Flatten each piece of dough into a circle. Wrap one biscuit around each apple half and place, seam side down, in pan.
In small bowl, combine sugar, water, melted butter and vanilla. Pour mixture over dumplings in pan. Sprinkle cinnamon on top. Bake 35 to 40 minutes, until golden. Serve hot.
