How is 2-(2-{2-[2-(Tetrahydro-2H-pyran-2-yloxy)ethoxy]ethoxy}ethoxy)ethyl 4-methylbenzenesulfonate (CAS: 86259-89-4) typically synthesized?

This compound is synthesized through a multistep process involving the introduction of tetrahydro-2H-pyran-2-yloxy onto ethylene glycol derivatives, followed by sulfonation with 4-methylbenzenesulfonic acid. Commonly used catalysts include hydrogen chloride in the sulfonation step, and the overall yield is around 85%. The reaction is typically conducted under anhydrous conditions to avoid side reactions.