Quantifying the efficiency of CO₂ capture by Lewis pairs

Abstract

A microfluidic strategy is used to assess the relative efficiency and thermodynamic parameters of CO2 binding by three Lewis acid/base combinations.

Accessing Frustrated Lewis Pair Chemistry from a Spectroscopically Stable and Classical Lewis Acid‐Base Adduct

“…In a similar fashion, the seemingly stable 2 reacted with other established FLP substrates including azides, sulfinylamines, and CO 2 . In all instances, these reactions gave FLP addition products (Scheme ).…”

“…Whereas classical FLPs such as t Bu 3 P/B(C 6 F 5 ) 3 ,r equire the simultaneous action of the Lewis acid and base on CO 2 to effect capture of this small molecule,the present system appears to react in as tepwise manner (Figure ). [14,17] While the formation of 1-CO 2 is not observable by NMR spectroscopy,i ta ppears this species is trapped by B(C 6 F 5 ) 3 . [14,17] While the formation of 1-CO 2 is not observable by NMR spectroscopy,i ta ppears this species is trapped by B(C 6 F 5 ) 3 .…”

“…[1b] In the absence of B(C 6 F 5 ) 3 , 1 is known to readily cyclotrimerize isocyanates into isocyanurates. [14] In all instances,t hese reactions gave FLP addition products (Scheme 2). [13] In as imilar fashion, the seemingly stable 2 reacted with other established FLP substrates including azides, [13b] sulfinylamines, [13a] and CO 2 .…”

“…[13] In as imilar fashion, the seemingly stable 2 reacted with other established FLP substrates including azides, [13b] sulfinylamines, [13a] and CO 2 . [14] In all instances,t hese reactions gave FLP addition products (Scheme 2). Specifically, 4 is the product of 1,3-addition across the N 3 group of PhCH 2 N 3 , 5 is that of 1,3-addition across the NSO functional group of PhNSO,a nd 6 is that of 1,2-addition across the C À Od ouble bond of CO 2 .T he identities of 4-6 were confirmed spectroscopically and crystallographically ( Figure 2).…”

Lewis and Brønsted basicity of phosphine-diazomethane derivatives

“…The reactions of frustrated Lewis pairs (FLPs) with small molecules has emerged as a strategy for reactivity. [1][2][3][4][5][6][7][8] While this work was initiated by the finding that combinations of Lewis acids and bases could activate H2, 9 this has expanded to encompass a wide range of small molecules including olefins, 10 alkynes, [11][12] disulfides, 13 N2O, [14][15] cyclopropanes, 16 CO2, [17][18] CO, [19][20] NO, 21 SO2 [22][23] and RNSO. 24 Such broad reactivity with substrates typically activated by transition-metal systems prompted the question: can FLP reactivity be extended to dinitrogen?…”