Activation of Carbon Dioxide by Silyl Triflate-Based Frustrated Lewis Pairs

Silyl triflates of the form R4−nSi(OTf)n (n=1, 2; OTf=OSO3CF3) are shown to activate carbon dioxide when paired with bulky alkyl‐substituted Group 15 bases. Combinations of silyl triflates and 2,2,6,6‐tetramethylpiperidine react with CO2 to afford silyl carbamates via a frustrated Lewis pair‐type mechanism. With trialkylphosphines, the silyl triflates R3Si(OTf) reversibly bind CO2 affording [R′3P(CO2)SiR3][OTf] whereas when Ph2Si(OTf)2 is used one or two molecules of CO2 can be sequestered. The latter bis‐CO2 product is favoured at low temperatures and by excess phosphine. Silyl triflates of the form R4−nSi(OTf)n (n=1, 2; OTf=OSO3CF3) were shown to activate carbon dioxide when paired with bulky alkyl‐substituted Group 15 bases. Combinations of silyl triflates and 2,2,6,6‐tetramethylpiperidine react with CO2 to afford silyl carbamates via a frustrated Lewis pair‐type mechanism.