Combine 1 1/2 cups water and sugar in a small saucepan over high heat. Cook until the sugar is dissolved, about 2 minutes. Cool the simply syrup completely. This simple syrup can be made 1 week in advance and stored, covered, in the refrigerator.
Combine the simple syrup, lemon juice and orange juice in a pitcher. Mix in the club soda. Add the lemon slices, orange slices and mint.
Fill glasses with crushed ice. Add 1 shot bourbon to each glass and fill to the top with the sparkling lemonade. Garnish each glass with mint.