Abstract
A water-tolerant frustrated Lewis pair (FLP) combines a sterically encumbered Lewis acid and Lewis base that in synergy are able to activate small molecules even in the presence of water. The main challenge introduced by water comes from its reversible coordination to the Lewis acid which causes a marked increase in the Bronsted acidity of water. Indeed, the oxophilic Lewis acids typically used in FLP chemistry form water adducts whose acidity can be comparable to that of strong Bronsted acids such as HCl, thus they can protonate the Lewis base component of the FLP. Irreversible proton transfer quenches the reactivity of both the Lewis acid and the Lewis base, precluding small molecule activation. This short review discusses the efforts to overcome water-intolerance in FLP systems, a topic that in less than five years has seen significant progress. 1 Introduction 2 Water-Tolerance (or Alcohol-Tolerance) in Carbonyl Reductions 3 Water-Tolerance with Stronger Bases 4 Water-Tolerant Non-Boron-Based Lewis Acids in FLP Chemistry 5 Conclusions.
Original language | English |
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Article number | ss-2018-z0059-sr |
Pages (from-to) | 1783-1795 |
Number of pages | 13 |
Journal | Synthesis (Germany) |
Volume | 50 |
Issue number | 9 |
Early online date | 29 Mar 2018 |
DOIs | |
Publication status | Published - 2 May 2018 |
Keywords
- frustrated Lewis pairs
- Lewis acid
- Lewis base
- reduction
- water-tolerance