The solubility of sucrose in water at 25 °C is given as 2000 g/L. But, that doesn't tell us if this solubility, given in units of g/L, is expressed as a molar concentration (aka molarity) or as a molality. That's because molarity and molality are equal for diluted solutes (which don't contribute much to the total mass of the solution), this does not hold for concentrations as high as 2000 g/L.
Thus, you have to turn to other sources, which are careful of specifying the quantity given:
Now that we're clear about what is specified, you can turn these quantities into any other you want. For example, if I understand the definition of degrees Brix correctly, we can get the following approximation: 1 liter of water has a mass of 1 kg, plus 2.1 kg of sucrose in it gives the solution a mass of 3.1 kg. So, given that you have 2.1 kg of sucrose in a 3.1 kg solution, you'd be at 68 °Bx.