Place chicken breast halves between 2 sheets plastic wrap or parchment paper, spacing apart.
Using mallet, pound chicken to 1/4-inch thickness.
Mix clementines and next 8 ingredients in medium bowl.
Season with salt and pepper.
Uncover chicken; sprinkle with salt and pepper.
Heat olive oil in large nonstick skillet over medium-high heat. Add chicken and cook until slightly browned and cooked through, about 3 minutes per side.
Transfer chicken to platter. Add clementine juice to skillet; boil until reduced to 1/4 cup, stirring often, about 2 minutes. Drizzle sauce over chicken. Spoon salsa over and serve.