Capture of NO by a Frustrated Lewis Pair: A New Type of Persistent N‐Oxyl Radical

Abstract

Mit NO gegen Frustration: Das intramolekulare frustrierte Lewis‐Paar (FLP) Mes2PCH2CH2B(C6F5)2 fängt NO unter Bildung des neuartigen N‐Oxylradikals P/B‐FLP‐NO. ab (siehe Schema). Nach der Koordination von NO an das FLP kann dieses H‐Atome aus Cyclohexen und Ethylbenzol abspalten, was zu P/B‐FLP‐NOH und der O‐funktionalisierten Spezies P/B‐FLP‐NOR führt.

Metal‐Free Hydrogenation of Unsaturated Hydrocarbons Employing Molecular Hydrogen

“…An alternative approach was reported by Wang et al, and it takes advantage of the well-known reactivity of olefins towards hydroboranes such as BH 3 , 9borabicyclo[3.3.1]nonane (9-BBN), or HB(C 6 F 5 ) 2 (12). As clearly seen from a mechanistic point of view the protonation of simple olefins will be more challenging.…”

“…[5] simplicity and clearness. The conserved reactivity of the Lewis pair can now be exploited for the activation or fixation of a number of small molecules, for example, CO 2 , [10] CO, SO 2 , [11] NO, [12] N 2 O, [13] and H 2 . [14] In fact, the activation of the latter has attracted the most attention because of the multifaceted application for hydrogenation reactions.…”

“…As clearly seen from a mechanistic point of view the protonation of simple olefins will be more challenging. An alternative approach was reported by Wang et al, and it takes advantage of the well-known reactivity of olefins towards hydroboranes such as BH 3 , 9borabicyclo[3.3.1]nonane (9-BBN), or HB(C 6 F 5 ) 2 (12). In the 1960s Ramp, DeWitt, and Trapasso reported the hydrogenation of select olefins in the presence of substoichiometric amounts of triisobutylborane with H 2 using 235 8C and 172 bar H 2 pressure.…”

Frustrated Lewis Pair Chemistry of Chiral (+)‐Camphor‐Based Aminoboranes

“…[1] Lewis acidic and basic centers in FLPs have unquenched reactivity that can be used in activation and splitting of small molecules, for example, CO 2 , [2] carbonyl compounds, [3] unsaturated hydrocarbons, [4] N 2 O, [5] and many others. [6] FLPs are able to split hydrogen heterolytically, [7] opening a way to catalytic hydrogenation of unsaturated organic substrates in the absence of metals. [8] Most of the FLPs studied so far employ substituted boranes and boryl groups as Lewis acidic counterparts.…”

Reaction of a 6‐Dimethylaminopentafulvene with the Mes2PCH2CH2B(C6F5)2 Frustrated Lewis Pair

“…[5] The P/B FLP even adds (reversibly) to carbon dioxide [6] and undergoes a 1,1-P/B addition reaction to nitric oxide (NO) to yield a novel type of a persistent N-oxyl radical, the new P/B-FLP NO system. [7] The FLP (1) was shown to undergo a series of interesting reactions with pentafulvenes, especially with regard to carbon-carbon bond formation and CÀC s-bond activation. We had found that 1 reacts with 6,6-dimethylpentafulvene in a slow reaction over several days to yield the FLP-addition product (2) to the fulvene [6+4] dimer [Eq.…”