SSC2025 Programme Booklet

Day 2: Plenary Lecture

Rewiring Sustainability: Navigating Complexity to Unlock the Power of Innovation Roselle-Simpor Main Ballroom 9 December 8:45am

Sean de Cleene Singapore Institute of Technology

Coming Soon.

Day 2: Keynote Lecture (Parallel Session 1)

Chiral Cationic Ion Pair Catalysis using Guanidiniums Roselle-Simpor 4601 9 December 9:50am

Choon Hong Tan Nanyang Technological University

Chiral cations have demonstrated exceptional efficacy as phase-transfer catalysts, particularly in conjunction with inorganic basic salts like hydroxides and carbonates in base-mediated reactions. Over the past decade, we have developed several chiral cation catalysts, notably pentanidium and bisguanidinium, which have significantly advanced the field. In this report, we explore their roles in ion-pair catalysis using three distinct types of anions. First, we examine the use of fluoride to generate hypervalent silicate intermediates and its pairing with chiral cations to facilitate enantioselective reactions. Next, we delve into reactions where chiral cations work synergistically with polyoxometalates, such as tungstate and molybdate, serving as co catalysts. Lastly, we highlight the ability of chiral cations to modulate reactions involving anionic organic sulfur salts. Key transformations, including SN2X (halogenophilic nucleophilic substitution) and the desymmetrization of sulfinates, will be discussed in detail.

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