You'd probably be fine, but why risk it? How much time does it really save? Are you perhaps waiting for the solution to cool back down before racking your beer onto it? If so, don't bother. I boil mine just long enough to dissolve the sugar, then I pour it into the bottling bucket and immediately begin racking beer onto it. Yes, it's still hot enough to kill yeast, but it's such a small amount that the first few ounces of beer will quickly cool it down to a safe range, such that there is more than enough living, healthy yeast in the rest of the beer to carry out bottle conditioning. This isn't just a theory, it's how I do it, and it's worked fine every time I've done it.
Make it the first thing you do on bottling day. Step 1: Pour water in pot, put on stove on high heat. While it's heating, pour Star San into the bottling bucket and swirl it around. Weigh out the priming sugar. Line up the bottles. Run some sanitizer through the siphon and bottling wand. Pull up a chair. Lift the fermenter into position. By now, your water should be boiling. Turn off the heat, mix in the sugar, dump the Star San from the bottling bucket, pour in the sugar solution, and start racking.