Some synthetic oil is made from recycled oil while other brands of synthetic oil may use fresh oil that has been pumped out of the ground and refined.
Some brands of oil may also use both recycled engine oil as well as fresh crude oil that is refined to make the synthetic oil.
It all depends on the oil manufacturer and what they do.
I've known some oils that are synthetic oils that are recycled oils while others are freshly made oil using non recycled oil.
Either way even recycled oil is just as good as non recycled oil as they clean the old oil of contaminants making it just as good for your engine as fresh oil that is non recycled would.