Frustrated Lewis pair modification by 1,1-carboboration: disclosure of a phosphine oxide triggered nitrogen monoxide addition to an intramolecular P/B frustrated Lewis pair.
The vicinal frustrated Lewis pair (FLP) mes2P-CH2CH2-B(C6F5)2 (3) reacts with phenyl(trimethylsilyl)acetylene by 1,1-carboboration to give the extended C3-bridged FLP 6 featuring a substituted vinylborane subunit. The FLP 6 actively cleaves dihydrogen. The FLP 3 also undergoes a 1,1-carboboration reaction with diphenylphosphino(trimethylsilyl)acetylene to give the P/B/P FLP 11 that features a central unsaturated four-membered heterocyclic P/B FLP and a pendant CH2CH2-Pmes2 functional group. Compound 11 reacts with nitric oxide (NO) by oxidation of the pendant Pmes2 unit to the P(O)mes2 phosphine oxide and N,N-addition of the P/B FLP unit to NO to yield the persistent P/B/PO FLPNO aminoxyl radical 14. This reaction is initiated by P(O)mes2 formation and opening of the central Ph2P···B(C6F5)2 linkage triggered by the pendant CH2CH2-P(O)mes2 group.
Organisch-Chemisches Institut, Universität Münster , Corrensstrasse 40, Münster 48149, Germany.
René
R
Liedtke
Felix
F
Scheidt
Jinjun
J
Ren
Birgitta
B
Schirmer
Allan Jay P
AJ
Cardenas
Constantin G
CG
Daniliuc
Hellmut
H
Eckert
Timothy H
TH
Warren
Stefan
S
Grimme
Gerald
G
Kehr
Gerhard
G
Erker