1361399-42-9

Upstream product

• 1221271-51-7 C₃₂H₁₂BF₂₄^(1-)*C₂₂H₄₅IrNO₂P₂⁽¹⁺⁾ 
• 1361399-31-6 [(2,6-(t-Bu₂PO)2C₅H₃N)Ir(ethylene)][tetrakis(3,5-bis(trifluoromethyl)phenyl)borate] 
• 1333-74-0 hydrogen 

Relevant academic research and scientific papers

Mechanism of hydrogenolysis of an iridium-methyl bond: Evidence for a methane complex intermediate

Evidence for key σ-complex intermediates in the hydrogenolysis of the iridium-methyl bond of (PONOP)Ir(H)(Me)+ (1) [PONOP = 2,6-bis(di-tert-butylphosphinito)pyridine] has been obtained. The initially formed η2-H2 complex, 2, was directly observed upon treatment of 1 with H2, and evidence for reversible formation of a σ-methane complex, 5, was obtained through deuterium scrambling from η2-D2 in 2-d2 into the methyl group of 2 prior to methane loss. This sequence of reactions was modeled by density functional theory calculations. The transition state for formation of 5 from 2 showed significant shortening of the Ir-H bond for the hydrogen being transferred; no true Ir(V) trihydride intermediate could be located. Barriers to methane loss from 2 were compared to those of 1 and the six-coordinate species (PONOP)Ir(H)(Me)(CO)+ and (PONOP)Ir(H)(Me)(Cl).

Dihydrogen complexes of iridium and rhodium

A series of iridium and rhodium pincer complexes have been synthesized and characterized: [(POCOP)Ir(H)(H2)] [BArf4] (1-H3), (POCOP)Rh(H2) (2-H2), [(PONOP)Ir(C 2H4)] [BArf4] (3-C2H 4), [(PONOP)Ir(H)2)] [BArf4] (3-H2), [(PONOP)Rh(C2H4)] [BArf 4] (4-C2H4) and [(PONOP)Rh(H2)] [BArf4] (4-H2) (POCOP = I3-C 6H3-2,6-[OP(tBu)2]2; PONOP = 2,6-(tBu2PO)2C5H3N; BAr f4 = tetrakis(3,5-trifluoromethylphenyl)borate). The nature of the dihydrogen-metal interaction was probed using NMR spectroscopic studies. Complexes 1-H3, 2-H2, and 4-H2 retain the H-H bond and are classified as η2-dihydrogen adducts. In contrast, complex 3-H2 is best described as a classical dihydride system. The presence of bound dihydrogen was determined using both T1 and 1JHD coupling values: T1 = 14 ms, 1JHD = 33 Hz for the dihydrogen ligand in 1-H3, T1(min) = 23 ms, 1JHD = 32 Hz for 2-H 2, T1(min) = 873 ms for 3-H2, T 1(min) = 33 ms, 1JHD = 30.1 Hz for 4-H 2.