Used primarily as an alkylating agent in organic synthesis, particularly in pharmaceutical manufacturing. It efficiently introduces cyclopropylmethyl groups into target molecules, making it valuable in the development of active pharmaceutical ingredients (APIs). Commonly employed in the preparation of opioid derivatives and other central nervous system agents due to the metabolic stability and bioavailability imparted by the cyclopropyl ring. Also utilized in research settings for modifying alkaloids and designing novel drug candidates. Its high reactivity requires careful handling, but it offers excellent selectivity under controlled conditions.